AGREEMENT AND PLAN OF REORGANIZATION
 
     This AGREEMENT AND PLAN OF  REORGANIZATION  (the  "Agreement")  is made and
entered into as of October 1st, 1996 among  Allegro New Media,  Inc., a Delaware
corporation ("Allegro"), SPC Acquisition Corporation, a Delaware corporation and
a wholly-owned  subsidiary of Allegro  ("Merger Sub"),  and Software  Publishing
Corporation, a Delaware corporation ("SPC").
 
                                    RECITALS
 
     A. Upon the terms and subject to the  conditions  of this  Agreement and in
accordance with the Delaware General  Corporation Law ("Delaware Law"),  Allegro
and SPC will enter into a business  combination  transaction  pursuant  to which
Merger Sub will merge with and into SPC (the "Merger").
 
     B. The Board of Directors of Allegro (i) has determined  that the Merger is
consistent with and in furtherance of the long-term business strategy of Allegro
and fair to, and in the best  interests of, Allegro and its  stockholders,  (ii)
has approved this Agreement, the Merger and the other transactions  contemplated
by this Agreement and (iii) has  recommended  that the  stockholders  of Allegro
vote to approve this Agreement.
 
     C. The Board of  Directors  of SPC (i) has  determined  that the  Merger is
consistent with and in furtherance of the long-term business strategy of SPC and
fair to,  and in the  best  interests  of,  SPC and its  stockholders,  (ii) has
approved this Agreement,  the Merger and the other transactions  contemplated by
this Agreement and (iii) has  recommended  the approval of this Agreement by the
stockholders of SPC.
 
     D.  Allegro  and Merger  Sub,  on the one hand,  and SPC on the other hand,
desire to make certain  representations  and warranties and other  agreements in
connection with the Merger.
 
     E. The parties  intend,  by executing  this  Agreement,  to adopt a plan of
reorganization within the meaning of Section 368 of the Internal Revenue Code of
1986, as amended (the "Code").
 
     NOW,   THEREFORE,   in  consideration   of  the  covenants,   promises  and
representations set forth herein, and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged,  the parties agree
as follows:
 
                                   ARTICLE I
 
                                   THE MERGER
 
     1.1 The  Merger.  At the  Effective  Time (as  defined in Section  1.2) and
subject  to and  upon  the  terms  and  conditions  of  this  Agreement  and the
applicable  provisions of Delaware Law, Merger Sub shall be merged with and into
SPC,  the separate  corporate  existence of Merger Sub shall cease and SPC shall
continue as the surviving  corporation.  SPC as the surviving  corporation after
the Merger is hereinafter sometimes referred to as the "Surviving Corporation."
 
     1.2 Effective Time;  Closing.  Subject to the provisions of this Agreement,
the  parties  hereto  shall  cause  the  Merger  to be  consummated  by filing a
Certificate of Merger (the  "Certificate of Merger") with the Secretary of State
of the State of Delaware in accordance with the relevant  provisions of Delaware
Law (the time of such  filing (or such later time as may be agreed in writing by
the parties and specified in the  Certificate  of Merger)  being the  "Effective
Time") as soon as practicable on or after the Closing Date (as herein  defined).
Unless the  context  otherwise  requires,  the term  "Agreement"  as used herein
refers collectively to this Agreement and the Certificate of Merger. The closing
of the Merger (the "Closing")  shall take place at the offices of Wilson Sonsini
Goodrich & Rosati,  Professional  Corporation at a time and date to be specified
by the parties,  which shall be no later than the second  business day after the
satisfaction  or waiver of the  conditions  set forth in Article  VI, or at such
other  time,  date and  location  as the parties  hereto  agree in writing  (the
"Closing Date").
 

<PAGE>

     1.3 Effect of the Merger.  At the Effective  Time, the effect of the Merger
shall be as provided in this Agreement and the applicable provisions of Delaware
Law. Without limiting the generality of the foregoing,  and subject thereto,  at
the Effective Time all the property, rights,  privileges,  powers and franchises
of SPC and Merger Sub shall vest in the  Surviving  Corporation,  and all debts,
liabilities and duties of SPC and Merger Sub shall become the debts, liabilities
and duties of the Surviving Corporation.
 
     1.4 Certificate of Incorporation; Bylaws.
 
     (a) At the Effective Time, the Certificate of  Incorporation of Merger Sub,
as in effect  immediately  prior to the Effective Time, shall be the Certificate
of  Incorporation  of the  Surviving  Corporation  until  thereafter  amended as
provided by law and such Certificate of Incorporation;  provided,  however, that
at the  Effective  Time  the  Certificate  of  Incorporation  of  the  Surviving
Corporation shall be amended so that the name of the Surviving Corporation shall
be "Software Publishing Corporation."
 
     (b) The  Bylaws  of  Merger  Sub,  as in  effect  immediately  prior to the
Effective  Time,  shall be, at the Effective  Time,  the Bylaws of the Surviving
Corporation until thereafter amended.
 
     1.5 Directors and Officers.  The directors of Merger Sub immediately  prior
to  the  Effective  Time  shall  be  the  initial  directors  of  the  Surviving
Corporation, until their respective successors are duly elected or appointed and
qualified.  The officers of Merger Sub  immediately  prior to the Effective Time
shall  be  the  initial  officers  of the  Surviving  Corporation,  until  their
successors are duly elected or appointed or qualified.
 
     1.6 Effect on Capital Stock. At the Effective Time, by virtue of the Merger
and without  any action on the part of Merger Sub,  SPC or the holders of any of
the following securities:
 
          (a) Conversion of SPC Capital Stock.  Each share of Common Stock, par
     value $.001 per share, of SPC (the "SPC Capital Stock") issued and
     outstanding immediately prior to the Effective Time (other than any shares
     of SPC Capital Stock to be canceled pursuant to Section 1.6(b) and any
     Dissenting Shares (as defined in and to the extent provided in Section
     1.7(a)) will be canceled and extinguished and automatically converted
     (subject to Sections 1.6(e) and (f)) into the right to receive 0.26805
     the "Exchange Ratio") shares of Common Stock, par value $.001 per share,
     of Allegro (the "Allegro Common Stock") upon surrender of the certificate
     representing such share of SPC Capital Stock in the manner provided in
     Section 1.8 (or in the case of a lost, stolen or destroyed certificate,
     upon delivery of an affidavit (and bond, if required) in the manner
     provided in Section 1.10).
 
          (b) Cancellation of Allegro-Owned Stock.  Each share of SPC Capital
     Stock held in the treasury of SPC or owned by Merger Sub, Allegro or any
     direct or indirect wholly owned subsidiary of SPC or of Allegro immediately
     prior to the Effective Time shall be canceled and extinguished without any
     conversion thereof.
 
          (c) Stock Options.  At the Effective Time all options to purchase SPC
     Capital Stock then outstanding under SPC's 1987 Stock Option Plan, 1989
     Stock Option Plan, and 1991 Stock Option Plan (collectively, the "SPC Stock
     Option Plans") shall be assumed by Allegro in accordance with Section 5.11
     hereof.
 
          (d) Employee Stock Purchase Plan.  With respect to the Company's
     Employee Stock Purchase Plan (the "SPC Employee Stock Purchase Plan"), the
     offering period currently in progress shall be shortened by setting a new
     exercise date which shall be the date immediately preceding the Effective
     Time (the "New Exercise Date"). The SPC Employee Stock Purchase Plan shall
     terminate immediately following the purchase of SPC Capital Stock on the
     New Exercise Date.
 

<PAGE>

          (e) Capital Stock of Merger Sub.  Each share of Common Stock, par
     value $.001 per share, of Merger Sub issued and outstanding immediately
     prior to the Effective Time shall be converted into and exchanged for one
     validly issued, fully paid and nonassessable share of Common Stock, par
     value $.001 per share, of the Surviving Corporation. Each stock certificate
     of Merger Sub evidencing ownership of any such shares shall continue to
     evidence ownership of such shares of capital stock of the Surviving
     Corporation.
 
          (f) Adjustments to Exchange Ratio.  The Exchange Ratio shall be
     adjusted to reflect fully the effect of any stock split, reverse stock
     split, stock dividend (including any dividend or distribution of
     securities convertible into Allegro Common Stock or SPC Capital Stock),
     reorganization, recapitalization or other like change with respect to
     Allegro Common Stock or SPC Capital Stock occurring on or after the date
     hereof and prior to the Effective Time.
 
          (g) Fractional Shares.  No fraction of a share of Allegro Common Stock
     will be issued by virtue of the Merger, but in lieu thereof each holder of
     shares of SPC Capital Stock who would otherwise be entitled to a fraction
     of a share of Allegro Common Stock (after aggregating all fractional shares
     of Allegro Common Stock to be received by such holder) shall receive from
     Allegro an amount of cash (rounded to the nearest whole cent) equal to the
     product of (i) such fraction, multiplied by (ii) the average closing price
     of a share of Allegro Common Stock for the ten most recent days that
     Allegro Common Stock has traded ending on the trading day immediately 
     prior to the Effective Time, as reported on the Nasdaq SmallCap Market.
 
     1.7 Dissenting Shares.
 
     (a)  Notwithstanding  any provision of this Agreement to the contrary,  the
shares  of any  holder  of SPC  Capital  Stock who has  demanded  and  perfected
appraisal  rights for such shares in accordance with Delaware Law and who, as of
the Effective Time, has not effectively  withdrawn or lost such appraisal rights
("Dissenting  Shares")  shall  not be  converted  into or  represent  a right to
receive  Allegro  Common Stock  pursuant to Section 1.6, but the holder  thereof
shall only be entitled to such rights as are granted by Delaware Law.
 
     (b) Notwithstanding  the foregoing,  if any holder of shares of SPC Capital
Stock who demands  appraisal of such shares under Delaware Law shall effectively
withdraw the right to appraisal, then, as of the later of the Effective Time and
the  occurrence  of such event,  such  holder's  shares shall  automatically  be
converted  into and represent  only the right to receive  Allegro  Common Stock,
without interest  thereon,  upon surrender of the certificate  representing such
shares.
 
     (c) SPC shall give  Allegro (i) prompt  notice of any  written  demands for
appraisal of any shares of SPC Capital Stock,  withdrawals of such demands,  and
any other instruments  served pursuant to Delaware Law and received by SPC which
relate to any such demand for appraisal and (ii) the  opportunity to participate
in all negotiations and proceedings which take place prior to the Effective Time
with respect to demands for appraisal  under Delaware Law. SPC shall not, except
with the prior  written  consent of Allegro or as may be required by  applicable
law,  voluntarily  make any payment with respect to any demands for appraisal of
SPC Capital Stock or offer to settle or settle any such demands.
 
     1.8 Surrender of Certificates.
 
     (a) Exchange Agent.  Allegro shall select American Stock Transfer and Trust
Company  or another  institution  reasonably  satisfactory  to SPC to act as the
exchange agent (the "Exchange Agent") in the Merger.
 
     (b) Allegro to Provide  Common Stock.  Promptly  after the Effective  Time,
Allegro  shall make  available to the Exchange  Agent for exchange in accordance
with this  Article I, the shares of Allegro  Common Stock  issuable  pursuant to
Section 1.6 in exchange for outstanding shares of SPC Capital Stock, and cash in
an amount  sufficient  for  payment in lieu of  fractional  shares  pursuant  to
Section 1.6(f) and any dividends or  distributions  and holders of shares of SPC
Capital Stock may be entitled pursuant to Section 1.8(d).
 

<PAGE>

     (c) Exchange  Procedures.  Promptly after the Effective Time, Allegro shall
cause the Exchange  Agent to mail to each holder of record (as of the  Effective
Time) of a certificate or certificates  (the  "Certificates")  which immediately
prior to the Effective Time represented  outstanding shares of SPC Capital Stock
whose shares were  converted  into the right to receive shares of Allegro Common
Stock pursuant to Section 1.6, cash in lieu of any fractional shares pursuant to
Section 1.6(f) and any dividends or other distributions pursuant to Section
1.8(d),  (i) a letter of transmittal (which shall specify that delivery shall be
effected,  and risk of loss and title to the Certificates  shall pass, only upon
delivery of the Certificates to the Exchange Agent and shall be in such form and
have  such  other  provisions  as  Allegro  may  reasonably  specify)  and  (ii)
instructions  for use in effecting the surrender of the Certificates in exchange
for certificates  representing  shares of Allegro Common Stock,  cash in lieu of
any  fractional  shares  pursuant to Section  1.6(f) and any  dividends or other
distributions  pursuant to Section  1.8(d).  Upon surrender of a Certificate for
cancellation  to the  Exchange  Agent or to such other agent or agents as may be
appointed by Allegro,  together with such letter of transmittal,  duly completed
and validly executed in accordance with the instructions  thereto, the holder of
such Certificate shall be entitled to receive in exchange therefor a certificate
representing the number of whole shares of Allegro Common Stock, payment in lieu
of  fractional  shares  which such  holder has the right to receive  pursuant to
Section 1.6(f) and any dividends or  distributions  payable  pursuant to Section
1.8(d), and the Certificate so surrendered shall forthwith be canceled. Until so
surrendered,  each  outstanding  Certificate  will be deemed  from and after the
Effective Time, for all corporate purposes,  subject to Section 1.8(d) as to the
payment of dividends,  to evidence the ownership of the number of full shares of
Allegro Common Stock into which such shares of SPC Capital Stock shall have been
so converted  and the right to receive an amount in cash in lieu of the issuance
of any fractional  shares in accordance with Section 1.6(f) and any dividends or
distributions payable pursuant to Section 1.8(d).
 
     (d) Distributions With Respect to Unexchanged Shares. No dividends or other
distributions  declared or made after the date of this Agreement with respect to
Allegro Common Stock with a record date after the Effective Time will be paid to
the  holder of any  unsurrendered  Certificate  with  respect  to the  shares of
Allegro  Common  Stock  represented  thereby  until the holder of record of such
Certificate  shall  surrender  such  Certificate.  Subject  to  applicable  law,
following  surrender of any such Certificate,  there shall be paid to the record
holder thereof  certificates  representing  whole shares of Allegro Common Stock
issued  in  exchange  therefor,  without  interest,  along  with the  amount  of
dividends or other  distributions  with a record date after the  Effective  Time
payable with respect to such whole shares of Allegro Common Stock.
 
     (e) Transfers of Ownership. If any certificate for shares of Allegro Common
Stock  is to be  issued  in a name  other  than  that in which  the  Certificate
surrendered in exchange  therefor is  registered,  it will be a condition of the
issuance thereof that the Certificate so surrendered  will be properly  endorsed
and  otherwise in proper form for transfer and that the person  requesting  such
exchange will have paid to Allegro or any agent designated by it any transfer or
other taxes  required by reason of the issuance of a  certificate  for shares of
Allegro Common Stock in any name other than that of the registered holder of the
Certificate  surrendered,  or established to the  satisfaction of Allegro or any
agent designated by it that such tax has been paid or is not payable.
 
     (f) No Liability.  Notwithstanding anything to the contrary in this Section
1.8,  neither the Exchange  Agent,  Allegro,  the Surviving  Corporation nor any
party  hereto  shall be liable to a holder of shares of Allegro  Common Stock or
SPC Capital Stock for any amount properly paid to a public official  pursuant to
any applicable abandoned property, escheat or similar law.
 

<PAGE>

     1.9 No Further Ownership Rights in SPC Capital Stock. All shares of Allegro
Common  Stock  issued  upon  the  surrender  for  exchange  of  Certificates  in
accordance  with the terms hereof  (including  any cash paid in respect  thereof
pursuant to Section  1.6(f) and  1.8(d))  shall be deemed to have been issued in
full  satisfaction of all rights pertaining to such shares of SPC Capital Stock,
and there shall be no further  registration  of  transfers on the records of the
Surviving  Corporation  of shares of SPC Capital  Stock  which were  outstanding
immediately   prior  to  the  Effective  Time.  If  after  the  Effective  Time,
Certificates  are presented to the Surviving  Corporation  for any reason,  they
shall be canceled and exchanged as provided in this Article I.
 
     1.10 Lost, Stolen or Destroyed Certificates.  In the event any Certificates
shall have been lost,  stolen or  destroyed,  the Exchange  Agent shall issue in
exchange for such lost, stolen or destroyed Certificates,  upon the making of an
affidavit  of that fact by the holder  thereof,  such whole  number of shares of
Allegro  Common  Stock  into  which the shares of SPC  Capital  Stock  evidenced
thereby shall have been converted, cash for fractional shares, if any, as may be
required  pursuant to Section 1.6(f) and any dividends or distributions  payable
pursuant  to  Section  1.8(d);  provided,  however,  that  Allegro  may,  in its
discretion  and as a condition  precedent to the issuance  thereof,  require the
owner of such lost,  stolen or destroyed  Certificates to deliver a bond in such
sum as it may reasonably  direct as indemnity against any claim that may be made
against Allegro or the Exchange Agent with respect to the  Certificates  alleged
to have been lost, stolen or destroyed.
 
     1.11 Tax and Accounting Consequences.  It is intended by the parties hereto
that the Merger shall constitute a reorganization  within the meaning of Section
368 of the  Code.  The  parties  hereto  adopt  this  Agreement  as a  "plan  of
reorganization"  within the meaning of Sections 1.368-2(g) and 1.368-3(a) of the
United States Income Tax Regulations.
 
     1.12 Taking of Necessary Action;  Further Action. If, at any time after the
Effective  Time,  any further  action is necessary or desirable to carry out the
purposes  of this  Agreement  and to vest the  Surviving  Corporation  with full
right, title and possession to all assets, property, rights, privileges,  powers
and  franchises  of SPC and Merger Sub, the  officers  and  directors of SPC and
Merger Sub are fully authorized in the name of their respective  corporations or
otherwise to take, and will take, all such lawful and necessary  action, so long
as such action is consistent with this Agreement.
 
                                   ARTICLE II
 
                      REPRESENTATIONS AND WARRANTIES OF SPC
 
     SPC  represents  and  warrants to Allegro  and Merger  Sub,  subject to the
exceptions  specifically  disclosed in writing in the disclosure letter supplied
by SPC to Allegro (the "SPC Schedules"), as follows:
 
     2.1  Organization  of SPC. SPC and each of its material  subsidiaries  is a
corporation duly organized, validly existing and in good standing under the laws
of the jurisdiction of its incorporation,  has the corporate power to own, lease
and operate its property and to carry on its business as now being conducted and
as proposed to be  conducted,  and is duly  qualified to do business and in good
standing as a foreign  corporation in each  jurisdiction in which the failure to
be so qualified would have a Material  Adverse Effect (as defined below) on SPC.
SPC  has  delivered  to  Allegro  a true  and  complete  list  of  all of  SPC's
subsidiaries, together with the jurisdiction of incorporation of each subsidiary
and SPC's equity  interest  therein.  SPC has delivered or made available a true
and  correct  copy of the  Certificate  of  Incorporation  and Bylaws of SPC and
similar governing  instruments of its subsidiaries,  each as amended to date, to
counsel  for  Allegro.  When used in  connection  with SPC,  the term  "Material
Adverse  Effect" means,  for purposes of this  Agreement,  any change,  event or
effect that is materially adverse to the business,  assets (including intangible
assets),   financial   condition  or  results  of  operations  of  SPC  and  its
subsidiaries  taken as a whole;  provided,  however,  that the  continuation  of
current trends in such business, assets (including intangible assets), financial
condition  or results of  operations  (including  without  limitation  declining
revenues  and  further  losses)  shall not be deemed to  constitute  a  Material
Adverse Effect,  but material  deviations  therefrom shall constitute a Material
Adverse Effect.
 

<PAGE>

     2.2 SPC Capital Structure.  The authorized capital stock of SPC consists of
30,000,000  shares of Common  Stock,  par value $.001 per share,  of which there
were  12,553,596  shares  issued and  outstanding  as of  October  1, 1996,  and
2,000,000 shares of Preferred  Stock,  par value $.001 per share,  none of which
are issued and outstanding as of October 1, 1996. All outstanding  shares of SPC
Capital Stock are duly authorized, validly issued, fully paid and non-assessable
and are not subject to preemptive rights created by statute,  the Certificate of
Incorporation  or Bylaws of SPC or any  agreement  or document to which SPC is a
party or by which it is bound.  As of  October  1,  1996,  SPC had  reserved  an
aggregate of 3,187,760 shares of Common Stock, net of exercises, for issuance to
employees,  consultants  and  non-employee  directors  pursuant to the SPC Stock
Option Plans,  under which options are outstanding for an aggregate of 3,018,725
shares.  All shares of SPC Capital Stock subject to issuance as aforesaid,  upon
issuance on the terms and conditions  specified in the  instruments  pursuant to
which they are issuable,  would be duly authorized,  validly issued,  fully paid
and  nonassessable.  The SPC Schedules list each  outstanding  option to acquire
shares of the Common Stock of SPC at October 1, 1996,  the name of the holder of
such option,  the number of shares subject to such option, the exercise price of
such  option,  the number of shares as to which such  option will have vested at
such date and whether the  exercisability  of such option will be accelerated in
any way by the  transactions  contemplated  by this  Agreement  or for any other
reason,  and indicate the extent of  acceleration,  if any. As of September  15,
1996, there were 10 participants in the SPC Employee Stock Purchase Plan.
 
     2.3  Obligations  With  Respect  to Capital  Stock.  Except as set forth in
Section  2.2,  there  are no  equity  securities  of any  class  of SPC,  or any
securities  exchangeable  or  convertible  into or  exercisable  for such equity
securities, issued, reserved for issuance or outstanding.  Except for securities
SPC owns, directly or indirectly through one or more subsidiaries,  there are no
equity  securities  of any  class  of any  subsidiary  of SPC,  or any  security
exchangeable  or  convertible  into or exercisable  for such equity  securities,
issued,  reserved  for issuance or  outstanding.  Except as set forth in Section
2.2, there are no options, warrants, equity securities, calls, rights (including
preemptive  rights),  commitments or agreements of any character to which SPC or
any of its subsidiaries is a party or by which it is bound obligating SPC or any
of its subsidiaries to issue, deliver or sell, or cause to be issued,  delivered
or sold, or repurchase,  redeem or otherwise  acquire,  or cause the repurchase,
redemption or acquisition,  of any shares of capital stock of SPC, or any of its
subsidiaries  or obligating  SPC or any of its  subsidiaries  to grant,  extend,
accelerate  the  vesting  of or  enter  into any such  option,  warrant,  equity
security, call, right, commitment or agreement. There are no registration rights
and,  to the  knowledge  of SPC,  there are no voting  trusts,  proxies or other
agreements or understandings with respect to any equity security of any class of
SPC  or  with  respect  to  any  equity  security  of  any  class  of any of its
subsidiaries.
 
     2.4 Authority.
 
     (a) SPC has all requisite  corporate power and authority to enter into this
Agreement and to consummate the transactions  contemplated hereby. The execution
and  delivery  of  this  Agreement  and  the  consummation  of the  transactions
contemplated hereby, have been duly authorized by all necessary corporate action
on the part of SPC,  subject  only to the  approval of this  Agreement  by SPC's
stockholders  and the  filing  and  recordation  of the  Certificate  of  Merger
pursuant  to  Delaware  Law. A vote of the holders of at least a majority of the
outstanding  shares of the SPC Capital Stock is required for SPC's  stockholders
to approve this  Agreement.  This Agreement has been duly executed and delivered
by SPC and,  assuming the due  authorization,  execution and delivery by Allegro
and, if applicable,  Merger Sub, constitutes the valid and binding obligation of
SPC,  enforceable in accordance with its terms,  except as enforceability may be
limited by bankruptcy  and other similar laws and general  principles of equity.
The  execution  and  delivery  of  this  Agreement  by SPC  does  not,  and  the
performance  of this Agreement by SPC will not, (i) conflict with or violate the
Certificate of Incorporation  or Bylaws of SPC or the equivalent  organizational
documents of any of its subsidiaries,  (ii) subject to obtaining the approval of

<PAGE>

SPC's  stockholders  of the Merger as contemplated in Section 5.2 and compliance
with the  requirements  set forth in  Section  2.4(b)  below,  conflict  with or
violate any law, rule,  regulation,  order, judgment or decree applicable to SPC
or any of its subsidiaries or by which its or any of their respective properties
is bound or affected,  or (iii) result in any breach of or  constitute a default
(or an event that with  notice or lapse of time or both would  become a default)
under,  or impair SPC's rights or alter the rights or  obligations  of any third
party  under,  or  give  to  others  any  rights  of   termination,   amendment,
acceleration  or  cancellation  of,  or  result  in the  creation  of a lien  or
encumbrance on any of the properties or assets of SPC or any of its subsidiaries
pursuant to, any note, bond, mortgage,  indenture,  contract,  agreement, lease,
license, permit, franchise or other instrument or obligation to which SPC or any
of its subsidiaries is a party or by which SPC or any of its subsidiaries or its
or any of their  respective  properties  are  bound or  affected,  except,  with
respect to clauses (ii) and (iii), for any such conflicts,  violations, defaults
or other  occurrences  that would not have a Material Adverse Effect on SPC. The
SPC Schedules  list all material  consents,  waivers and approvals  under any of
SPC's or any of its  subsidiaries'  agreements,  contracts,  licenses  or leases
required to be obtained in connection with the  consummation of the transactions
contemplated hereby.
 
     (b) No  consent,  approval,  order or  authorization  of, or  registration,
declaration  or filing with any court,  administrative  agency or  commission or
other  governmental  authority  or  instrumentality  ("Governmental  Entity") is
required by or with respect to SPC in connection with the execution and delivery
of this Agreement or the consummation of the transactions contemplated hereby or
thereby,  except for (i) the filing of a Form S-4  Registration  Statement  (the
"Registration Statement") with the Securities and Exchange Commission ("SEC") in
accordance with the Securities Act of 1933, as amended (the  "Securities  Act"),
(ii) the filing of the  Certificate of Merger with the Secretary of State of the
State of  Delaware,  (iii) the  filing of the Proxy  Statement  (as  defined  in
Section 2.20) with the SEC in  accordance  with the  Securities  Exchange Act of
1934, as amended (the  "Exchange  Act"),  (iv) the filing of a Current Report on
Form 8-K with the SEC, (v) such  consents,  approvals,  orders,  authorizations,
registrations,  declarations  and  filings as may be required  under  applicable
federal and state  securities  laws and the laws of any foreign country and (vi)
such other consents, authorizations, filings, approvals and registrations which,
if not  obtained  or made,  would not have a Material  Adverse  Effect on SPC or
Allegro  or have a material  adverse  effect on the  ability  of the  parties to
consummate the Merger.
 
     2.5 Section 203 of the Delaware General Corporation Law Not Applicable. The
Board of  Directors  of SPC has  taken  all  actions  so that  the  restrictions
contained in Section 203 of the Delaware General Corporation Law applicable to a
"business  combination"  (as  defined  in  Section  203)  will not  apply to the
execution,  delivery or performance of this Agreement or to the  consummation of
the Merger or the other transactions contemplated by this Agreement.
 
     2.6 SEC Filings; SPC Financial Statements.
 
     (a) SPC has filed all forms,  reports  and  documents  required to be filed
with the SEC since  October  1, 1994,  and has made  available  to Allegro  such
forms,  reports and  documents in the form filed with the SEC. All such required
forms,  reports and documents  (including  those that SPC may file subsequent to
the date  hereof) are  referred to herein as the "SPC SEC  Reports." As of their
respective  dates,  the SPC SEC Reports (i) were prepared in accordance with the
requirements  of the Securities Act or the Exchange Act, as the case may be, and
the rules  and  regulations  of the SEC  thereunder  applicable  to such SPC SEC
Reports,  and  (ii)  did not at the time  they  were  filed  (or if  amended  or
superseded by a filing prior to the date of this Agreement,  then on the date of
such filing) contain any untrue  statement of a material fact or omit to state a
material  fact  required to be stated  therein or necessary in order to make the
statements  therein,  in the light of the  circumstances  under  which they were
made, not misleading.  None of SPC's subsidiaries is required to file any forms,
reports or other documents with the SEC.
 

<PAGE>

     (b) Each of the consolidated financial statements (including, in each case,
any related notes thereto)  contained in SPC SEC Reports (the "SPC Financials"),
including any SPC SEC Reports filed after the date hereof until the Closing, (x)
complied  as to form in all  material  respects  with the  published  rules  and
regulations of the SEC with respect thereto, (y) was prepared in accordance with
generally accepted accounting  principles ("GAAP") applied on a consistent basis
throughout the periods involved (except as may be indicated in the notes thereto
or, in the case of unaudited interim financial  statements,  as may be permitted
by the SEC on Form 10-Q under the  Exchange  Act) and (z) fairly  presented  the
consolidated financial position of SPC and its subsidiaries as at the respective
dates thereof and the consolidated  results of its operations and cash flows for
the periods  indicated,  except that the unaudited interim financial  statements
were or are subject to normal and recurring year-end adjustments which were not,
or are not  expected  to be,  material  in  amount.  The  balance  sheet  of SPC
contained in SPC SEC Reports as of June 30, 1996 is  hereinafter  referred to as
the "SPC Balance Sheet." Except as disclosed in the SPC Financials,  neither SPC
nor any of its subsidiaries has any liabilities (absolute,  accrued,  contingent
or otherwise) of a nature  required to be disclosed on a balance sheet or in the
related notes to the consolidated  financial  statements  prepared in accordance
with GAAP which are, individually or in the aggregate, material to the business,
results of operations or financial  condition of SPC and its subsidiaries  taken
as a whole,  except  liabilities  (i) provided for in the SPC Balance Sheet,  or
(ii) incurred since the date of the SPC Balance Sheet in the ordinary  course of
business consistent with past practices.
 
     (c) SPC has heretofore  furnished to Allegro a complete and correct copy of
any amendments or modifications,  which have not yet been filed with the SEC but
which are required to be filed,  to agreements,  documents or other  instruments
which  previously  had been filed by SPC with the SEC pursuant to the Securities
Act or the Exchange Act.
 
     2.7 Absence of Certain Changes or Events. Since the date of the SPC Balance
Sheet through the date of this  Agreement,  there has not been: (i) any Material
Adverse  Effect  on SPC,  (ii)  any  material  change  by SPC in its  accounting
methods,  principles or practices,  except as required by concurrent  changes in
GAAP,  or (iii) any  revaluation  by SPC of any of its assets  having a Material
Adverse Effect on SPC, including, without limitation,  writing down the value of
capitalized  software or inventory  or writing off notes or accounts  receivable
other than in the ordinary course of business.
 
     2.8  Taxes.  SPC and each of its  subsidiaries  has filed  all tax  returns
required  to be  filed  by any of them  and  has  paid  (or SPC has  paid on its
behalf),  or has set up an adequate  reserve  for the  payment of, all  material
taxes  required  to be paid  as  shown  on such  returns,  and the  most  recent
financial  statements  contained  in the SPC SEC  Reports  reflect  an  adequate
reserve  for all  material  taxes  payable by SPC and its  subsidiaries  accrued
through the date of such financial statements. Except as reasonably would not be
expected to have a Material Adverse Effect on SPC, no deficiencies for any taxes
have been proposed, asserted or assessed against SPC or any of its subsidiaries.
For the purpose of this  Agreement,  the term "tax" shall  include all  Federal,
state, local and foreign income, profits,  franchise,  gross receipts,  payroll,
sales, employment, use, property, withholding, excise and other taxes, duties or
assessments of any nature whatsoever,  together with all interest, penalties and
additions imposed with respect to such amounts.
 
     2.9 Intellectual Property.
 
     (a) To the knowledge of SPC and its subsidiaries,  SPC and its subsidiaries
own, or have the right to use,  sell or license all patents,  trademarks,  trade
names,  service marks,  copyrights and other intellectual  property necessary or
required for the conduct of their respective  businesses as presently  conducted
(such intellectual  property and the rights thereto are collectively referred to
herein as the "SPC IP Rights"),  except for any failure to own or have the right
to use,  sell or license that would not have a Material  Adverse  Effect on SPC;
provided, that the foregoing exception shall not apply to the SPC IP Rights with
respect to "Intelligent Formatting".
 

<PAGE>

     (b) The  execution,  delivery and  performance  of this  Agreement  and the
consummation  of the  transactions  contemplated  hereby will not  constitute  a
breach of any  instrument or agreement  governing any SPC IP Rights (the "SPC IP
Rights  Agreements"),  will not cause the forfeiture or termination or give rise
to a right of forfeiture or termination of any SPC IP Rights or impair the right
of SPC and its subsidiaries,  the Surviving  Corporation or Allegro to use, sell
or license any SPC IP Rights or portion  thereof,  except for the  occurrence of
any  such  breach,   forfeiture,   termination  or  impairment  that  would  not
individually or in the aggregate, result in a Material Adverse Effect on SPC.
 
     (c)  To  the  knowledge  of SPC  and  its  subsidiaries,  (i)  neither  the
manufacture,  marketing,  license,  sale  or  intended  use  of any  product  or
technology  currently licensed or sold or under development by SPC or any of its
subsidiaries  violates  any  license  or  agreement  between  SPC  or any of its
subsidiaries and any third party or infringes any intellectual property right of
any other  party;  and (ii) there is no  pending  or, to the  knowledge  of SPC,
threatened claim,  arbitration or litigation contesting the validity,  ownership
or right to use,  sell,  license or  dispose  of any SPC IP Rights,  nor has SPC
received  any written  notice  asserting  that any SPC IP Rights or the proposed
use, sale,  license or disposition  thereof  conflicts or will conflict with the
rights of any other party, except, with respect to clauses (i) and (ii), for any
violations,  infringements,  claims or litigation that would not have a Material
Adverse Effect on SPC.
 
     (d) SPC has taken  reasonable and  practicable  steps designed to safeguard
and maintain the secrecy and  confidentiality of, and its proprietary rights in,
all SPC IP Rights.
 
     2.10 Compliance; Permits; Restrictions.
 
     (a) Neither SPC nor any of its  subsidiaries  is in  conflict  with,  or in
default or  violation  of, (i) any law,  rule,  regulation,  order,  judgment or
decree  applicable to SPC or any of its  subsidiaries  or by which its or any of
their  respective  properties  is bound or  affected,  or (ii) any  note,  bond,
mortgage,  indenture,  contract, agreement, lease, license, permit, franchise or
other  instrument  or obligation  to which SPC or any of its  subsidiaries  is a
party  or by  which  SPC  or  any of  its  subsidiaries  or its or any of  their
respective properties is bound or affected,  except for any conflicts,  defaults
or  violations  which  would  not have a  Material  Adverse  Effect  on SPC.  No
investigation  or review by any  governmental or regulatory body or authority is
pending or, to the knowledge of SPC, threatened against SPC or its subsidiaries,
nor has any governmental or regulatory body or authority  indicated an intention
to conduct the same,  other than, in each such case,  those the outcome of which
would not have a Material Adverse Effect on SPC.
 
     (b)  SPC  and its  subsidiaries  hold  all  permits,  licenses,  variances,
exemptions,  orders  and  approvals  from  governmental  authorities  which  are
material to the operation of the business of SPC and its subsidiaries taken as a
whole  (collectively,  the  "SPC  Permits").  SPC  and its  subsidiaries  are in
compliance  with the terms of SPC Permits,  except where the failure to hold the
same or to so comply would not have a Material Adverse Effect on SPC.
 
     2.11 Litigation.  There is no action, suit, proceeding,  claim, arbitration
or  investigation  pending,  or as to which SPC or any of its  subsidiaries  has
received any notice of  assertion  nor, to SPC's  knowledge,  is there a written
threat of an action,  suit,  proceeding,  claim,  arbitration  or  investigation
against  SPC or any of its  subsidiaries  which  would have a  Material  Adverse
Effect on SPC, or which in any manner  challenges  or seeks to prevent,  enjoin,
alter or delay any of the transactions contemplated by this Agreement.
 
     2.12  Brokers'  and  Finders'  Fees.  Except for fees  payable to Unterberg
Harris disclosed to Allegro, SPC has not incurred,  nor will it incur,  directly
or  indirectly,  any  liability  for  brokerage  or  finders'  fees  or  agents'
commissions  or any similar  charges in  connection  with this  Agreement or any
transaction contemplated hereby.
 

<PAGE>

     2.13 Employee Benefit Plans.
 
     (a)  With  respect  to  each  material  employee  benefit  plan,   program,
arrangement and contract (including,  without limitation,  any "employee benefit
plan" as defined in Section 3(3) of the Employee  Retirement Income Security Act
of 1974, as amended ("ERISA"))  maintained or contributed to by SPC or any trade
or business (an "ERISA Affiliate") which is under common control with SPC within
the meaning of Section 414 of the Code (the "SPC Employee Plans"),  SPC has made
available to Allegro a true and complete copy of, to the extent applicable,  (i)
such SPC Employee  Plan,  (ii) the most recent annual report (Form 5500),  (iii)
each trust  agreement  related to such SPC Employee  Plan,  (iv) the most recent
summary plan description for each SPC Employee Plan for which such a description
is required,  (v) the most recent  actuarial report relating to any SPC Employee
Plan  subject  to Title IV of ERISA  and  (vi)  the most  recent  United  States
Internal Revenue Service ("IRS") determination letter issued with respect to any
SPC Employee Plan.
 
     (b) Each SPC Employee Plan which is intended to be qualified  under Section
401(a) of the Code has received a favorable  determination from the IRS covering
the provisions of the Tax Reform Act of 1986 stating that such SPC Employee Plan
is so  qualified  and  nothing has  occurred  since the date of such letter that
could  reasonably be expected to affect the qualified  status of such plan. Each
SPC Employee Plan has been operated in all material  respects in accordance with
its terms and the  requirements  of  applicable  law.  Neither SPC nor any ERISA
Affiliate  of SPC has incurred or is  reasonably  expected to incur any material
liability under Title IV of ERISA in connection with any SPC Employee Plan.
 
     (c) Neither SPC nor any ERISA Affiliate thereof has withdrawn in a complete
or partial withdrawal from any multi-employer plan within the meaning of Section
4001(a)(3)  of ERISA  prior to the  Effective  Time.  Neither  SPC nor any ERISA
Affiliate  thereof has  contributed  to or been  obligated to  contribute to any
multi-employer plan within the meaning of Section 4001(a)(3) of ERISA.
 
     2.14 Absence of Liens and  Encumbrances.  SPC and each of its  subsidiaries
has good and valid  title to, or, in the case of leased  properties  and assets,
valid  leasehold  interests  in, all of its  material  tangible  properties  and
assets,  real,  personal and mixed, used in its business,  free and clear of any
liens or  encumbrances  except as reflected in the SPC Financials and except for
liens for  taxes not yet due and  payable  and such  imperfections  of title and
encumbrances, if any, which would not have a Material Adverse Effect on SPC.
 
     2.15 Environmental Matters.
 
     (a) Hazardous Material.  Except as would not have a Material Adverse Effect
on SPC, no  underground  storage tanks and no amount of any  substance  that has
been designated by any Governmental  Entity or by applicable  federal,  state or
local law to be radioactive, toxic, hazardous or otherwise a danger to health or
the environment,  including,  without  limitation,  PCBs,  asbestos,  petroleum,
urea-formaldehyde  and all substances listed as hazardous substances pursuant to
the Comprehensive  Environmental  Response,  Compensation,  and Liability Act of
1980, as amended,  or defined as a hazardous waste pursuant to the United States
Resource  Conservation and Recovery Act of 1976, as amended, and the regulations
promulgated  pursuant to said laws,  (a  "Hazardous  Material"),  but  excluding
office and janitorial supplies, are present in the soil,  groundwater,  building
materials  or ambient air of any real  property  currently  occupied by SPC as a
result of the deliberate actions of SPC or any of its subsidiaries,  and SPC has
not  received  any  notice  that it is  allegedly  liable  for the  presence  of
Hazardous  Materials in, on or under any other property,  including the land and
the improvements, ground water and surface water thereof, that SPC or any of its
subsidiaries has at any time owned, operated, occupied or leased.
 
     (b)  Hazardous  Materials  Activities.  Except as would not have a Material
Adverse Effect on SPC,  neither SPC nor any of its subsidiaries has transported,
stored,  used,  manufactured,  disposed of, released or exposed its employees or
others to Hazardous Materials in violation of any law in effect on or before the
Closing Date, nor has SPC or any of its subsidiaries  disposed of,  transported,
sold, or manufactured any product containing a Hazardous Material  (collectively
"Hazardous Materials Activities") in violation of any rule,  regulation,  treaty
or statute  promulgated by any  Governmental  Entity in effect prior to or as of
the date hereof to  prohibit,  regulate or control  Hazardous  Materials  or any
Hazardous Material Activity.
 

<PAGE>

     (c) Permits.  SPC and its  subsidiaries  currently  hold all  environmental
approvals,  permits,  licenses,  clearances and consents (the "SPC Environmental
Permits")  necessary  for the conduct of SPC's and its  subsidiaries'  Hazardous
Material  Activities as currently  conducted and other businesses of SPC and its
subsidiaries as such  activities and businesses are currently  being  conducted,
except where the failure to so hold would not have a Material  Adverse Effect on
SPC.
 
     (d) Environmental Liabilities.  No material action, proceeding,  revocation
proceeding,  amendment  procedure,  writ,  injunction or claim is pending, or to
SPC's  knowledge,  threatened  concerning  any SPC  Environmental  Permit or any
Hazardous Materials Activity of SPC or any of its subsidiaries. SPC is not aware
of any fact or circumstance  which could involve SPC or any of its  subsidiaries
in any  environmental  litigation or impose upon SPC or any of its  subsidiaries
any environmental liability that would have a Material Adverse Effect on SPC.
 
     2.16  Labor  Matters.  To  SPC's  knowledge,  there  are no  activities  or
proceedings  of any labor union to organize  any  employees of SPC or any of its
subsidiaries and there are no strikes, or material slowdowns,  work stoppages or
lockouts,  or threats  thereof by or with respect to any employees of SPC or any
of its  subsidiaries.  SPC and its  subsidiaries are and have been in compliance
with all applicable laws regarding employment practices, terms and conditions of
employment,  and wages  and  hours  (including,  without  limitation,  ERISA (as
defined  below),  WARN or any  similar  state  or  local  law),  except  for any
noncompliance that would not have a Material Adverse Effect on SPC.
 
     2.17 Agreements,  Contracts and Commitments. Except as set forth in the SPC
Schedules, neither SPC nor any of its subsidiaries is a party to or is bound by:
 
          (a) any collective bargaining agreements;
 
          (b) any bonus, deferred compensation, incentive compensation, pension,
     profit-sharing or retirement plans, or any other employee benefit plans or
     arrangements;
 
          (c) any employment or consulting agreement, contract or commitment
     with any officer or director level employee, not terminable by SPC or any
     of its subsidiaries on thirty days notice without liability, except to the
     extent general principles of wrongful termination law may limit SPC's or
     any of its subsidiaries, ability to terminate employees at will;
 
          (d) any agreement or plan, including, without limitation, any stock
     option plan, stock appreciation right plan or stock purchase plan, any of
     the benefits of which will be increased, or the vesting of benefits of
     which will be accelerated, by the occurrence of any of the transactions
     contemplated by this Agreement or the value of any of the benefits of which
     will be calculated on the basis of any of the transactions contemplated by
     this Agreement;
 
          (e) any agreement of indemnification or guaranty not entered into in
     the ordinary course of business other than indemnification agreements
     between SPC or any of its subsidiaries and any of its officers or
     directors;
 
          (f) any agreement, contract or commitment containing any covenant
     limiting the freedom of SPC or any of its subsidiaries to engage in any
     line of business or compete with any person;
 
          (g) any agreement, contract or commitment relating to capital
     expenditures and involving future obligations in excess of $50,000 and not
     cancelable without penalty;
 

<PAGE>

          (h) any agreement, contract or commitment currently in force relating
     to the disposition or acquisition of assets not in the ordinary course of
     business or any ownership interest in any corporation, partnership, joint
     venture or other business enterprise;
 
          (i) any mortgages, indentures, loans or credit agreements, security
     agreements or other agreements or instruments relating to the borrowing of
     money or extension of credit;
 
          (j) any joint marketing or development agreement (excluding agreements
     with resellers, value added resellers or independent software vendors
     entered into in the ordinary course of business that do not permit such
     resellers or vendors to modify SPC's or any of its subsidiaries' software
     products);
 
          (k) any distribution agreement (identifying any that contain
     exclusivity provisions); or
 
          (l) any other agreement, contract or commitment (excluding real and
     personal property leases) which involve payment by SPC or any of its
     subsidiaries under any such agreement, contract or commitment of $50,000 or
     more in the aggregate and is not cancelable without penalty within thirty
     (30) days.
 
     Neither SPC nor any of its  subsidiaries,  nor to SPC's knowledge any other
party to an SPC Contract (as defined below), has breached, violated or defaulted
under, or received notice that it has breached  violated or defaulted under, any
of the  material  terms or  conditions  of any of the  agreements,  contracts or
commitments  to  which  SPC is a party  or by  which  it is  bound  of the  type
described  in clauses  (a) through  (l) above (any such  agreement,  contract or
commitment,  an "SPC Contract") in such a manner as would permit any other party
to cancel or terminate any such SPC Contract, or would permit any other party to
seek damages, which would have a Material Adverse Effect on SPC.
 
     2.18 Change of Control Payments.  There are no plans or agreements pursuant
to which any amounts may become payable (whether  currently or in the future) to
current or former  officers or directors of SPC as a result of or in  connection
with the Merger.
 
     2.19 Statements;  Proxy  Statement/Prospectus.  The information supplied by
SPC for inclusion in the  Registration  Statement (as defined in Section 2.4(b))
shall not, at the time the  Registration  Statement is filed with the SEC and at
the time it becomes  effective  under the  Securities  Act,  contain  any untrue
statement of a material  fact or omit to state any material  fact required to be
stated  therein  or  necessary  in  order  to make the  statements  therein  not
misleading.  The  information  supplied  by  SPC  for  inclusion  in  the  proxy
statement/prospectus  to be sent to the  stockholders of SPC and stockholders of
Allegro in  connection  with the meeting of SPC's  stockholders  to consider the
approval of this Agreement (the "SPC  Stockholders'  Meeting") and in connection
with the meeting of  Allegro's  stockholders  to consider  the  approval of this
Agreement (the "Allegro Stockholders' Meeting") (such proxy statement/prospectus
as amended or supplemented is referred to herein as the "Proxy Statement") shall
not, on the date the Proxy Statement is first mailed to SPC's  stockholders  and
Allegro's  stockholders,  at the time of the SPC  Stockholders'  Meeting  or the
Allegro  Stockholders'  Meeting and at the  Effective  Time,  contain any untrue
statement of a material  fact or omit to state any material  fact required to be
stated therein or necessary in order to make the statements therein, in light of
the circumstances under which they are made, not false or misleading; or omit to
state any  material  fact  necessary  to correct  any  statement  in any earlier
communication   with  respect  to  the  solicitation  of  proxies  for  the  SPC
Stockholders'  Meeting or the  Allegro  Stockholders'  Meeting  which has become
false or misleading.  The Proxy Statement will comply as to form in all material
respects with the  provisions of the Exchange Act and the rules and  regulations
thereunder.  If at any time prior to the Effective  Time,  any event relating to
SPC or any of its affiliates,  officers or directors should be discovered by SPC
which  should be set forth in an amendment  to the  Registration  Statement or a
supplement  to  the  Proxy   Statement,   SPC  shall  promptly  inform  Allegro.
Notwithstanding  the  foregoing,  SPC makes no  representation  or warranty with
respect to any information  supplied by Allegro or Merger Sub which is contained
in any of the foregoing documents.
 

<PAGE>

     2.20 Board  Approval.  The Board of Directors of SPC has, as of the date of
this  Agreement,  determined  (i)  that  the  Merger  is fair to and in the best
interests  of  SPC  and  its  stockholders,  and  (ii)  to  recommend  that  the
stockholders of SPC approve this Agreement.
 
     2.21 Minute  Books.  The minute books of SPC made  available to counsel for
Allegro  are the only  minute  books of SPC and  contain a  reasonably  accurate
summary,  in all material respects,  of all meetings of directors (or committees
thereof)  and  stockholders  or  actions by  written  consent  since the time of
incorporation of SPC.
 
                                   ARTICLE III
 
            REPRESENTATIONS AND WARRANTIES OF ALLEGRO AND MERGER SUB
 
     Allegro  and  Merger  Sub  represent  and  warrant  to SPC,  subject to the
exceptions  specifically  disclosed in the disclosure letter supplied by Allegro
to SPC (the "Allegro Schedules"), as follows:
 
     3.1 Organization of Allegro.  Allegro and each of its material subsidiaries
is a corporation duly organized, validly existing and in good standing under the
laws of the jurisdiction of its  incorporation,  has the corporate power to own,
lease  and  operate  its  property  and to carry on its  business  as now  being
conducted and as proposed to be conducted,  and is duly qualified to do business
and in good standing as a foreign  corporation in each jurisdiction in which the
failure to be so  qualified  would have a Material  Adverse  Effect (as  defined
below) on Allegro.  Allegro has delivered to SPC a true and complete list of all
of Allegro's  subsidiaries,  together with the  jurisdiction of incorporation of
each subsidiary and Allegro's equity interest therein.  Allegro has delivered or
made available a true and correct copy of the Certificate of  Incorporation  and
Bylaws of Allegro and similar governing instruments of its subsidiaries, each as
amended to date, to counsel for SPC. When used in connection  with Allegro,  the
term  "Material  Adverse  Effect"  means,  for purposes of this  Agreement,  any
change,  event or effect  that is  materially  adverse to the  business,  assets
(including  intangible assets),  financial condition or results of operations of
Allegro  and its  subsidiaries  taken as a whole;  provided,  however,  that the
continuation of current trends in such business,  assets  (including  intangible
assets),  financial  condition  or  results  of  operations  (including  without
limitation  further losses) shall not be deemed to constitute a Material Adverse
Effect,  but material  deviations  therefrom shall constitute a Material Adverse
Effect.
 
     3.2 Allegro  Capital  Structure.  The  authorized  capital stock of Allegro
consists of  18,000,000  shares of Common Stock,  par value $.001 per share,  of
which there were 4,444,477  shares issued and outstanding as of October 1, 1996,
2,000,000 shares of Class A Preferred Stock, par value $.001 per share, of which
there were no shares issued and outstanding as of October 1, 1996, 60,520 shares
of Class B Voting  Preferred  Stock,  par value $.001 per share,  of which there
were 60,520  shares issued and  outstanding  as of October 1, 1996 and 1,939,480
shares of Serial  Preferred Stock, par value $.001 per share, of which no shares
were issued or outstanding  as of October 1, 1996. The authorized  capital stock
of Merger Sub  consists  of 1,000  shares of Common  Stock,  par value $.001 per
share,  100 shares of which,  as of the date hereof,  are issued and outstanding
and are held by Allegro.  All outstanding  shares of the Common Stock of Allegro
are duly authorized,  validly issued,  fully paid and non-assessable and are not
subject  to  preemptive   rights   created  by  statute,   the   Certificate  of
Incorporation or Bylaws of Allegro or any agreement or document to which Allegro
is a party or by which it is bound. As of October 1, 1996,  Allegro had reserved
an aggregate of 1,500,000 shares of Common Stock, net of exercises, for issuance
to employees,  consultants and non-employee directors pursuant to Allegro's 1994
Long-Term  Incentive  Plan and Allegro's  Outside  Directors and Advisors  Stock
Option Plan  (collectively,  the  "Allegro  Stock  Option  Plans"),  under which
options are outstanding  for an aggregate  1,106,115  shares.  All shares of the

<PAGE>

Common Stock of Allegro subject to issuance as aforesaid,  upon issuance on
the terms and conditions specified in the instruments pursuant to which they are
issuable,   would  be  duly   authorized,   validly   issued,   fully  paid  and
nonassessable.  The Allegro  Schedules list each  outstanding  option to acquire
shares of the Common Stock  Allegro at June 30, 1996,  the name of the holder of
such option,  the number of shares subject to such option, the exercise price of
such  option,  the number of shares as to which such  option will have vested at
such date and whether the  exercisability  of such option will be accelerated in
any way by the  transactions  contemplated  by this  Agreement  or for any other
reason, and indicate the extent of acceleration, if any.
 
     3.3  Obligations  With  Respect  to Capital  Stock.  Except as set forth in
Section  3.2,  there are no equity  securities  of any class of Allegro,  or any
securities  exchangeable  or  convertible  into or  exercisable  for such equity
securities, issued, reserved for issuance or outstanding.  Except for securities
Allegro owns, directly or indirectly through one or more subsidiaries, there are
no equity securities of any class of any subsidiary of Allegro,  or any security
exchangeable  or  convertible  into or exercisable  for such equity  securities,
issued,  reserved  for issuance or  outstanding.  Except as set forth in Section
3.2, there are no options, warrants, equity securities, calls, rights (including
preemptive rights),  commitments or agreements of any character to which Allegro
or any of its subsidiaries is a party or by which it is bound obligating Allegro
or any of its  subsidiaries  to issue,  deliver or sell,  or cause to be issued,
delivered or sold,  or  repurchase,  redeem or otherwise  acquire,  or cause the
repurchase, redemption or acquisition, of any shares of capital stock of Allegro
or any of its  subsidiaries or obligating  Allegro or any of its subsidiaries to
grant, extend, accelerate the vesting of or enter into any such option, warrant,
equity security, call, right, commitment or agreement. There are no registration
rights and, to the knowledge of Allegro there are no voting  trusts,  proxies or
other  agreements or  understandings  with respect to any equity security of any
class of Allegro or with  respect to any equity  security of any class of any of
its subsidiaries.
 
     3.4 Authority.
 
     (a) Each of Allegro and Merger Sub has all  requisite  corporate  power and
authority  to enter  into this  Agreement  and to  consummate  the  transactions
contemplated  hereby.  The  execution  and  delivery of this  Agreement  and the
consummation of the transactions  contemplated  hereby have been duly authorized
by all  necessary  corporate  action on the part of Allegro  and, in the case of
this  Agreement,  Merger  Sub,  subject  only to the  approval  of the merger by
Allegro's  stockholders  as  contemplated  in  Section  5.2 and the  filing  and
recordation  of the  Certificate  of  Merger  pursuant  to  Delaware  Law.  This
Agreement has been duly executed and delivered by each of Allegro and Merger Sub
and, assuming the due authorization, execution and delivery of this Agreement by
SPC, this  Agreement  constitutes  the valid and binding  obligations of each of
Allegro and Merger Sub,  enforceable  in  accordance  with its terms,  except as
enforceability  may be limited by bankruptcy  and other similar laws and general
principles of equity.  The  execution and delivery of this  Agreement by each of
Allegro and Merger Sub do not, and the  performance of this Agreement by each of
Allegro and Merger Sub will not, (i) conflict with or violate the Certificate of
Incorporation or Bylaws of Allegro or the Certificate of Incorporation or Bylaws
of Merger Sub or the  equivalent  organizational  documents  of any of its other
subsidiaries,  (ii) subject to obtaining the approval of the Merger by Allegro's
stockholders as contemplated in Section 5.2 and compliance with the requirements
set forth in Section  3.4(b)  below,  conflict  with or violate  any law,  rule,
regulation,  order,  judgment  or decree  applicable  to  Allegro  or any of its
subsidiaries  (including  Merger Sub) or by which its or any of their respective
properties is bound or affected,  or (iii) result in any breach of or constitute
a default (or an event that with notice or lapse of time or both would  become a

<PAGE>

default) under, or impair Allegro's rights or alter the rights or obligations of
any third party under, or give to others any rights of  termination,  amendment,
acceleration  or  cancellation  of,  or  result  in the  creation  of a lien  or
encumbrance  on  any  of the  properties  or  assets  of  Allegro  or any of its
subsidiaries  (including  Merger Sub)  pursuant  to, any note,  bond,  mortgage,
indenture,  contract,  agreement,  lease,  license,  permit,  franchise or other
instrument or obligation to which Allegro or any of its subsidiaries  (including
Merger  Sub)  is a  party  or by  which  Allegro  or any of  its  sub  sidiaries
(including Merger Sub) or its or any of their respective properties are bound or
affected,  except,  with  respect  to  clauses  (ii)  and  (iii),  for any  such
conflicts,  violations,  defaults  or other  occurrences  that  would not have a
Material  Adverse  Effect on Allegro.  The Allegro  Schedules  list all material
consents,   waivers  and  approvals  under  any  of  Allegro's  or  any  of  its
subsidiaries' agreements,  contracts, licenses or leases required to be obtained
in connection with the consummation of the transactions contemplated hereby.

     (b) No  consent,  approval,  order or  authorization  of, or  registration,
declaration  or  filing  with any  Governmental  Entity is  required  by or with
respect to Allegro or Merger Sub in  connection  with the execution and delivery
of this Agreement or the consummation of the transactions  contemplated  hereby,
except  for  (i)  the  filing  of the  Registration  Statement  with  the SEC in
accordance with the Securities Act, (ii) the filing of the Certificate of Merger
with the  Secretary of State of the State of  Delaware,  (iii) the filing of the
Proxy  Statement  with the SEC in  accordance  with the Exchange  Act,  (iv) the
filing of a  Current  Report on Form 8-K with the SEC,  (v) the  listing  of the
Allegro  Common  Stock  on the  Nasdaq  SmallCap  Market,  (vi)  such  consents,
approvals, orders,  authorizations,  registrations,  declarations and filings as
may be required under applicable  federal and state securities laws and the laws
of any foreign country and (vii) such other consents,  authorizations,  filings,
approvals and  registrations  which,  if not obtained or made,  would not have a
Material  Adverse Effect on SPC or Allegro or have a material  adverse effect on
the ability of the parties to consummate the Merger.
 
     3.5 Section 203 of the Delaware General Corporation Law Not Applicable. The
Board of  Directors  of Allegro has taken all  actions so that the  restrictions
contained in Section 203 of the Delaware General Corporation Law applicable to a
"business  combination"  (as  defined  in  Section  203)  will not  apply to the
execution,  delivery or performance of this Agreement or to the  consummation of
the Merger or the other transactions contemplated by this Agreement.
 
     3.6 SEC Filings; Allegro Financial Statements.
 
     (a) Allegro has filed all forms, reports and documents required to be filed
with the SEC since and including  December  1995,  and has made available to SPC
such  forms,  reports  and  documents  in the form filed with the SEC.  All such
required  forms,  reports and documents  (including  those that Allegro may file
subsequent  to the date  hereof)  are  referred  to herein as the  "Allegro  SEC
Reports."  As of their  respective  dates,  the  Allegro  SEC  Reports  (i) were
prepared  in  accordance  with the  requirements  of the  Securities  Act or the
Exchange  Act,  as the case may be,  and the  rules and  regulations  of the SEC
thereunder  applicable to such Allegro SEC Reports, and (ii) did not at the time
they were filed (or if amended or  superseded  by a filing  prior to the date of
this Agreement, then on the date of such filing) contain any untrue statement of
a material fact or omit to state a material  fact required to be stated  therein
or  necessary  in order  to make the  statements  therein,  in the  light of the
circumstances  under which they were made,  not  misleading.  None of  Allegro's
subsidiaries is required to file any forms,  reports or other documents with the
SEC.
 
     (b) Each of the consolidated financial statements (including, in each case,
any related  notes  thereto)  contained  in Allegro SEC  Reports  (the  "Allegro
Financials"),  including  any Allegro  SEC  Reports  filed after the date hereof
until the Closing,  (x) complied as to form in all  material  respects  with the
published  rules  and  regulations  of the SEC  with  respect  thereto,  (y) was
prepared in accordance with generally accepted  accounting  principles  ("GAAP")
applied on a consistent  basis throughout the periods involved (except as may be
indicated in the notes  thereto or, in the case of unaudited  interim  financial
statements,  as may be  permitted  by the SEC on Form 10-QSB  under the Exchange
Act) and (z) fairly presented the consolidated financial position of Allegro and
its subsidiaries as at the respective dates thereof and the consolidated results
of its  operations  and cash flows for the  periods  indicated,  except that the
unaudited  interim  financial  statements  were or are  subject  to  normal  and

<PAGE>

recurring  year-end  adjustments  which  were not,  or are not  expected  to be,
material  in amount.  The  balance  sheet of Allegro  contained  in Allegro  SEC
Reports as of June 30, 1996 is hereinafter  referred to as the "Allegro  Balance
Sheet." Except as disclosed in the Allegro  Financials,  neither Allegro nor any
of its  subsidiaries  has any  liabilities  (absolute,  accrued,  contingent  or
otherwise)  of a nature  required to be disclosed  on a balance  sheet or in the
related notes to the consolidated  financial  statements  prepared in accordance
with GAAP which are, individually or in the aggregate, material to the business,
results of  operations  or financial  condition of Allegro and its  subsidiaries
taken as a whole,  except  liabilities  (i) provided for in the Allegro  Balance
Sheet,  or (ii)  incurred  since the date of the  Allegro  Balance  Sheet in the
ordinary course of business consistent with past practices.
 
     (c) Allegro has heretofore  furnished to SPC a complete and correct copy of
any amendments or modifications,  which have not yet been filed with the SEC but
which are required to be filed,  to agreements,  documents or other  instruments
which  previously  had  been  filed by  Allegro  with  the SEC  pursuant  to the
Securities Act or the Exchange Act.
 
     3.7  Absence of Certain  Changes or Events.  Since the date of the  Allegro
Balance Sheet through the date of this  Agreement,  there has not been:  (i) any
Material  Adverse Effect on Allegro,  (ii) any material change by Allegro in its
accounting  methods,  principles or practices,  except as required by concurrent
changes in GAAP, or (iii) any revaluation by Allegro of any of its assets having
a Material Adverse Effect on Allegro,  including,  without  limitation,  writing
down the value of  capitalized  software  or  inventory  or writing off notes or
accounts receivable other than in the ordinary course of business.
 
     3.8 Taxes.  Allegro and each of its  subsidiaries has filed all tax returns
required  to be filed by any of them  and has paid (or  Allegro  has paid on its
behalf),  or has set up an adequate  reserve  for the  payment of, all  material
taxes required to be paid as shown on such returns and the most recent financial
statements  contained in the Allegro SEC Reports reflect an adequate reserve for
all material taxes payable by Allegro and its  subsidiaries  accrued through the
date of such financial statements. Except as reasonably would not be expected to
have a Material  Adverse Effect on Allegro,  no deficiencies  for any taxes have
been proposed, asserted or assessed against Allegro or any of its subsidiaries.
 
     3.9 Intellectual Property.
 
     (a) To the  knowledge  of Allegro  and its  subsidiaries,  Allegro  and its
subsidiaries  own,  or have  the  right to use,  sell or  license  all  patents,
trademarks,  trade  names,  service  marks,  copyrights  and other  intellectual
property necessary or required for the conduct of their respective businesses as
presently  conducted  (such  intellectual  property  and the rights  thereto are
collectively  referred  to herein as the  "Allegro IP  Rights"),  except for any
failure to own or have the right to use,  sell or license  that would not have a
Material Adverse Effect on Allegro.
 
     (b) The  execution,  delivery and  performance  of this  Agreement  and the
consummation  of the  transactions  contemplated  hereby will not  constitute  a
breach of any  instrument  or  agreement  governing  any  Allegro IP Rights (the
"Allegro IP Rights Agreements"), will not cause the forfeiture or termination or
give rise to a right of  forfeiture or  termination  of any Allegro IP Rights or
impair the right of Allegro  and its  subsidiaries  to use,  sell or license any
Allegro IP Rights or portion  thereof,  except  for the  occurrence  of any such
breach, forfeiture,  termination or impairment that would not individually or in
the aggregate, result in a Material Adverse Effect on Allegro.
 
     (c) To the  knowledge  of Allegro  and its  subsidiaries,  (i)  neither the
manufacture,  marketing,  license,  sale  or  intended  use  of any  product  or
technology  currently licensed or sold or under development by Allegro or any of
its subsidiaries violates any license or agreement between Allegro or any of its
subsidiaries and any third party or infringes any intellectual property right of
any other party;  and (ii) there is no pending or, to the  knowledge of Allegro,
threatened claim,  arbitration or litigation contesting the validity,  ownership
or right to use,  sell,  license or dispose  of any  Allegro IP Rights,  nor has
Allegro  received any written notice asserting that any Allegro IP Rights or the
proposed use, sale,  license or disposition  thereof  conflicts or will conflict
with the rights of any other  party,  except,  with  respect to clauses  (i) and
(ii), for any  violations,  infringements,  claims or litigation  that would not
have a Material Adverse Effect on Allegro.
 

<PAGE>

     (d)  Allegro  has  taken  reasonable  and  practicable  steps  designed  to
safeguard and maintain the secrecy and  confidentiality  of, and its proprietary
rights in, all Allegro IP Rights.
 
     3.10 Compliance; Permits; Restrictions.
 
     (a) Neither Allegro nor any of its  subsidiaries is in conflict with, or in
default or  violation  of, (i) any law,  rule,  regulation,  order,  judgment or
decree  applicable to Allegro or any of its  subsidiaries or by which its or any
of their  respective  properties is bound or affected,  or (ii) any note,  bond,
mortgage,  indenture,  contract, agreement, lease, license, permit, franchise or
other  instrument or obligation to which Allegro or any of its subsidiaries is a
party  or by which  Allegro  or any of its  subsidiaries  or its or any of their
respective properties is bound or affected,  except for any conflicts,  defaults
or  violations  which would not have a Material  Adverse  Effect on Allegro.  No
investigation  or review by any  governmental  or, to the  knowledge of Allegro,
regulatory  body or authority is pending or  threatened  against  Allegro or its
subsidiaries, nor has any governmental or regulatory body or authority indicated
an  intention  to conduct  the same,  other than,  in each such case,  those the
outcome of which would not have a Material Adverse Effect on Allegro.

     (b) Allegro and its  subsidiaries  hold all permits,  licenses,  variances,
exemptions,  orders  and  approvals  from  governmental  authorities  which  are
material to the operation of the business of Allegro and its subsidiaries  taken
as a whole (collectively,  the "Allegro Permits").  Allegro and its subsidiaries
are in compliance with the terms of Allegro Permits, except where the failure to
hold the same or to so  comply  would  not have a  Material  Adverse  Effect  on
Allegro.
 
     3.11 Litigation.  There is no action, suit, proceeding,  claim, arbitration
or investigation  pending, or as to which Allegro or any of its subsidiaries has
received any notice of assertion nor, to Allegro's knowledge, is there a written
threat of an action,  suit,  proceeding,  claim,  arbitration  or  investigation
against Allegro or any of its  subsidiaries  which would have a Material Adverse
Effect  on  Allegro,  or which in any  manner  challenges  or seeks to  prevent,
enjoin, alter or delay any of the transactions contemplated by this Agreement.
 
     3.12 Brokers' and Finders'  Fees.  Except for fees payable to Frost Capital
Partners, Inc. and Joseph Abrams disclosed to SPC, Allegro has not incurred, nor
will it incur,  directly or indirectly,  any liability for brokerage or finders'
fees or agents'  commissions  or any  similar  charges in  connection  with this
Agreement or any transaction contemplated hereby.
 
     3.13 Employee Benefit Plans.
 
     (a)  With  respect  to  each  material  employee  benefit  plan,   program,
arrangement and contract (including,  without limitation,  any "employee benefit
plan" as defined in  Section  3(3) of ERISA)  maintained  or  contributed  to by
Allegro  or any ERISA  Affiliate  thereof  which is under  common  control  with
Allegro  within the  meaning of Section 414 of the Code (the  "Allegro  Employee
Plans"),  Allegro has made  available to SPC a true and complete copy of, to the
extent  applicable,  (i) such Allegro Employee Plan, (ii) the most recent annual
report (Form 5500),  (iii) each trust agreement related to such Allegro Employee
Plan, (iv) the most recent summary plan  description  for each Allegro  Employee
Plan for which such a  description  is required,  (v) the most recent  actuarial
report  relating to any Allegro  Employee  Plan subject to Title IV of ERISA and
(vi) the most recent IRS determination letter issued with respect to any Allegro
Employee Plan.
 
     (b) Each  Allegro  Employee  Plan which is intended to be  qualified  under
Section 401(a) of the Code has received a favorable  determination  from the IRS
covering the  provisions of the Tax Reform Act of 1986 stating that such Allegro
Employee  Plan is so qualified  and nothing has occurred  since the date of such
letter that could  reasonably be expected to affect the qualified status of such
plan. Each Allegro  Employee Plan has been operated in all material  respects in
accordance  with its terms  and the  requirements  of  applicable  law.  Neither
Allegro  nor any ERISA  Affiliate  of  Allegro  has  incurred  or is  reasonably
expected to incur any material  liability  under Title IV of ERISA in connection
with any Allegro Employee Plan.
 

<PAGE>

     (c) Neither  Allegro nor any ERISA  Affiliate  thereof has  withdrawn  in a
complete or partial withdrawal from any  multi-employer  plan within the meaning
of Section  4001(a)(3) of ERISA prior to the Effective Time. Neither Allegro nor
any ERISA  Affiliate  thereof has contributed to or been obligated to contribute
to any multi-employer plan within the meaning of Section 4001(a)(3) of ERISA.
 
     3.14  Absence  of  Liens  and   Encumbrances.   Allegro  and  each  of  its
subsidiaries  has good and valid title to, or, in the case of leased  properties
and  assets,  valid  leasehold  interests  in,  all  of  its  material  tangible
properties and assets, real, personal and mixed, used in its business,  free and
clear of any liens or encumbrances except as reflected in the Allegro Financials
and except for liens for taxes not yet due and payable and such imperfections of
title and  encumbrances,  if any, which would not have a Material Adverse Effect
on Allegro.
 
     3.15 Environmental Matters.
 
     (a) Hazardous Material.  Except as would not have a Material Adverse Effect
on  Allegro,  no  underground  storage  tanks and no  Hazardous  Materials  (but
excluding office and janitorial supplies) are present in the soil, ground water,
building  materials or ambient air of any real  property  currently  occupied by
SPC,  as  a  result  of  the  deliberate  actions  of  Allegro  or  any  of  its
subsidiaries,  and Allegro  has not  received  any notice  that it is  allegedly
liable  for the  presence  of  Hazardous  Materials  in,  on or under  any other
property,  including  the land and the  improvements,  ground  water and surface
water thereof, that Allegro has at any time owned, operated, occupied or leased.
 
     (b)  Hazardous  Materials  Activities.  Except as would not have a Material
Adverse  Effect on  Allegro,  neither  Allegro nor any of its  subsidiaries  has
transported,  stored, used,  manufactured,  disposed of, released or exposed its
employees or others to Hazardous  Materials in violation of any law in effect on
or before the Closing Date, nor has Allegro or any of its  subsidiaries  engaged
in any  Hazardous  Materials  Activities  in violation of any rule,  regulation,
treaty or statute  promulgated by any Governmental  Entity in effect prior to or
as of the date hereof to prohibit,  regulate or control  Hazardous  Materials or
any Hazardous Material Activity.
 
     (c) Permits.  Allegro and its subsidiaries currently hold all environmental
approvals,   permits,   licenses,   clearances   and  consents   (the   "Allegro
Environmental   Permits")  necessary  for  the  conduct  of  Allegro's  and  its
subsidiaries'  Hazardous  Material  Activities as currently  conducted and other
businesses of Allegro and its subsidiaries as such activities and businesses are
currently being conducted,  except where the failure to so hold would not have a
Material Adverse Effect on Allegro.
 
     (d) Environmental Liabilities.  No material action, proceeding,  revocation
proceeding,  amendment  procedure,  writ,  injunction or claim is pending, or to
Allegro's knowledge,  threatened  concerning any Allegro Environmental Permit or
any Hazardous Materials Activity of Allegro or any of its subsidiaries.  Allegro
is not aware of any fact or  circumstance  which could involve Allegro or any of
its subsidiaries in any  environmental  litigation or impose upon Allegro or any
of its  subsidiaries  any  environmental  liability  that  would have a Material
Adverse Effect on Allegro.
 
     3.16 Labor  Matters.  To Allegro's  knowledge,  there are no  activities or
proceedings  of any labor union to organize  any  employees of Allegro or any of
its subsidiaries and there are no strikes, or material slowdowns, work stoppages
or lockouts,  or threats  thereof by or with respect to any employees of Allegro
or any of its  subsidiaries.  Allegro and its  subsidiaries are and have been in
compliance with all applicable laws regarding  employment  practices,  terms and
conditions of employment,  and wages and hours (including,  without  limitation,
ERISA,  WARN or any similar  state or local law),  except for any  noncompliance
that would not have a Material Adverse Effect on Allegro.
 
     3.17  Agreements,  Contracts  and  Commitments.  Except as set forth in the
Allegro Schedules,  neither Allegro nor any of its subsidiaries is a party to or
is bound by:
 
          (a) any collective bargaining agreements;
 
          (b) any bonus, deferred compensation, incentive compensation, pension,
     profit-sharing or retirement plans, or any other employee benefit plans or
     arrangements;
 

<PAGE>

          (c) any employment or consulting agreement, contract or commitment
     with any officer or director level employee, not terminable by Allegro or
     any of its subsidiaries on thirty days notice without liability, except to
     the extent general principles of wrongful termination law may limit
     Allegro's or any of its subsidiaries' ability to terminate employees at
     will;
 
          (d) any agreement or plan, including, without limitation, any stock
     option plan, stock appreciation right plan or stock purchase plan, any of
     the benefits of which will be increased, or the vesting of benefits of
     which will be accelerated, by the occurrence of any of the transactions
     contemplated by this Agreement or the value of any of the benefits of which
     will be calculated on the basis of any of the transactions contemplated by
     this Agreement;
 
          (e) any agreement of indemnification or guaranty not entered into in
     the ordinary course of business other than indemnification agreements
     between Allegro or any of its subsidiaries and any of its officers or
     directors;
 
          (f) any agreement, contract or commitment containing any covenant
     limiting the freedom of Allegro or any of its subsidiaries to engage in any
     line of business or compete with any person;
 
          (g) any agreement, contract or commitment relating to capital
     expenditures and involving future obligations in excess of $50,000 and not
     cancelable without penalty;
 
          (h) any agreement, contract or commitment currently in force relating
     to the disposition or acquisition of assets not in the ordinary course of
     business or any ownership interest in any corporation, partnership, joint
     venture or other business enterprise;
 
          (i) any mortgages, indentures, loans or credit agreements, security
     agreements or other agreements or instruments relating to the borrowing of
     money or extension of credit;
 
          (j) any joint marketing or development agreement (excluding agreements
     with resellers, value added resellers or independent software vendors
     entered into in the ordinary course of business that do not permit such
     resellers or vendors to modify Allegro's or any of its subsidiaries'
     software products);
 
          (k) any distribution agreement (identifying any that contain
     exclusivity provisions); or
 
          (l) any other agreement, contract or commitment (excluding real and
     personal property leases) which involves payment by Allegro or any of its
     subsidiaries under any such agreement, contract or commitment of $50,000 or
     more in the aggregate and is not cancelable without penalty within thirty
     (30) days.
 
     Neither Allegro nor any of its subsidiaries, nor to Allegro's knowledge any
other party to an Allegro Contract (as defined below), has breached, violated or
defaulted  under, or received notice that it has breached  violated or defaulted
under,  any  of the  material  terms  or  conditions  of any of the  agreements,
contracts or  commitments to which Allegro is a party or by which it is bound of
the type  described  in  clauses  (a)  through  (l) above  (any such  agreement,
contract or commitment,  an "Allegro Contract") in such a manner as would permit
any other  party to cancel or  terminate  any such  Allegro  Contract,  or would
permit any other  party to seek  damages,  which  would have a Material  Adverse
Effect on Allegro.
 
     3.18 Change of Control Payments.  There are no plans or agreements pursuant
to which any material  amounts may become payable  (whether  currently or in the
future) to current or former  officers or directors of Allegro as a result of or
in connection with the Merger.
 
     3.19 Statements;  Proxy  Statement/Prospectus.  The information supplied by
Allegro  for  inclusion  in the  Registration  Statement  (as defined in Section
2.4(b)) shall not at the time the  Registration  Statement is filed with the SEC
and at the time it becomes  effective  under the  Securities  Act,  contain  any
untrue  statement of a material fact or omit to state any material fact required

<PAGE>

to be stated  therein or necessary in order to make the  statements  therein not
misleading.  The  information  supplied  by Allegro for  inclusion  in the Proxy
Statement to be sent to the  stockholders of Allegro and the stockholders of SPC
in  connection  with the Allegro  Stockholders'  Meeting  and SPC  Stockholders'
Meeting shall not, on the date the Proxy  Statement is first mailed to Allegro's
stockholders  and  SPC's  stockholders,  at the  time of the  SPC  Stockholders'
Meeting or the Allegro  Stockholders' Meeting and at the Effective Time, contain
any untrue  statement  of a  material  fact or omit to state any  material  fact
required  to be stated  therein  or  necessary  in order to make the  statements
therein,  in light of the circumstances  under which they are made, not false or
misleading;  or omit to  state  any  material  fact  necessary  to  correct  any
statement  in any earlier  communication  with  respect to the  solicitation  of
proxies for the Allegro  Stockholders'  Meeting or the SPC Stockholders' Meeting
which has become false or misleading. The Proxy Statement will comply as to form
in all material  respects with the  provisions of the Exchange Act and the rules
and  regulations  thereunder.  If at any time prior to the Effective  Time,  any
event relating to Allegro or any of its affiliates, officers or directors should
be  discovered  by  Allegro  which  should be set forth in an  amendment  to the
Registration  Statement or a supplement  to the Proxy  Statement,  Allegro shall
promptly   inform  SPC.   Notwithstanding   the  foregoing,   Allegro  makes  no
representation or warranty with respect to any information supplied by SPC which
is contained in any of the foregoing documents.
 
     3.20 Board Approval.  The Board of Directors of Allegro has, as of the date
of this  Agreement,  determined  (i) that the  Merger is fair to and in the best
interests  of  Allegro  and its  stockholders,  and (ii) to  recommend  that the
stockholders of Allegro approve this Agreement.
 
     3.21 Minute  Books.  The minute books of Allegro made  available to counsel
for SPC are the only minute books of Allegro and contain a  reasonably  accurate
summary,  in all material respects,  of all meetings of directors (or committees
thereof)  and  stockholders  or  actions by  written  consent  since the time of
incorporation of Allegro.
 
                                   ARTICLE IV
 
                       CONDUCT PRIOR TO THE EFFECTIVE TIME
 
     4.1 Conduct of Business.  During the period from the date of this Agreement
and continuing  until the earlier of the termination of this Agreement  pursuant
to its terms or the Effective  Time, SPC (which for the purposes of this Article
4 shall  include SPC and each of its  subsidiaries)  and Allegro  (which for the
purposes of this Article 4 shall include  Allegro and each of its  subsidiaries)
agree,  except  (i) in the  case  of SPC as  provided  in  Article  4 of the SPC
Schedules  and in the case of Allegro as  provided  in Article 4 of the  Allegro
Schedules, or (ii) to the extent that the other party shall otherwise consent in
writing,  to  carry on its  business  diligently  and in  accordance  with  good
commercial  practice  and to carry on its  business  in the usual,  regular  and
ordinary course,  in substantially the same manner as heretofore  conducted,  to
pay its debts and taxes when due subject to good faith  disputes over such debts
or taxes,  to pay or perform other  material  obligations  when due, and use its
commercially  reasonable  efforts consistent with past practices and policies to
preserve intact its present business  organization,  keep available the services
of its present  officers  and  employees  and preserve  its  relationships  with
customers, suppliers, distributors,  licensors, licensees, and others with which
it has  business  dealings.  In  furtherance  of the  foregoing  and  subject to
applicable  law, SPC and Allegro  agree to confer,  as promptly as  practicable,
prior to taking any material actions or making any material management decisions
with respect to the conduct of business. In addition,  except in the case of SPC
as  provided  in  Article 4 of the SPC  Schedules  and in the case of Allegro as
provided  in  Article 4 of the  Allegro  Schedules,  without  the prior  written
consent of the other, not to be unreasonably  withheld,  neither SPC nor Allegro
shall do any of the  following,  and neither SPC nor  Allegro  shall  permit its
subsidiaries to do any of the following:
 
          (a) Waive any stock repurchase rights, accelerate, amend or change the
     period of exercisability of options or restricted stock, or reprice options
     granted under any employee, consultant or director stock plans or authorize
     cash payments in exchange for any options granted under any of such plans;
 

<PAGE>

          (b) Enter into any material partnership arrangements, joint
     development agreements or strategic alliances;
 
          (c) Grant any severance or termination pay to any officer or employee
     except payments in amounts consistent with policies and past practices or
     pursuant to written agreements outstanding, or policies existing, on the
     date hereof and as previously disclosed in writing to the other, or adopt
     any new severance plan;
 
          (d) Transfer or license to any person or entity or otherwise extend,
     amend or modify in any material respect any rights to the SPC IP Rights or
     the Allegro IP Rights, as the case may be, or enter into grants to future
     patent rights, other than in the ordinary course of business;
 
          (e) Declare or pay any dividends on or make any other distributions
     (whether in cash, stock or property) in respect of any capital stock or
     split, combine or reclassify any capital stock or issue or authorize the
     issuance of any other securities in respect of, in lieu of or in
     substitution for any capital stock;
 
          (f) Repurchase or otherwise acquire, directly or indirectly, any
     shares of capital stock except pursuant to rights of repurchase of any such
     shares under any employee, consultant or director stock plan;
 
          (g) Issue, deliver, sell, authorize or propose the issuance, delivery
     or sale of, any shares of capital stock or any securities convertible into
     shares of capital stock, or subscriptions, rights, warrants or options to
     acquire and shares of capital stock or any securities convertible into
     shares of capital stock, or enter into other agreements or commitments of
     any character obligating it to issue any such shares or convertible
     securities, other than (i) the issuance of shares of SPC Capital Stock or
     Allegro Common Stock, as the case may be, pursuant to the exercise of stock
     options therefor outstanding as of the date of this Agreement, (ii) options
     to purchase shares of SPC Capital Stock or Allegro Common Stock, as the
     case may be, to be granted at fair market value in the ordinary course of
     business, consistent with past practice and in accordance with existing
     stock option plans, (iii) shares of SPC Capital Stock or Allegro Common
     Stock, as the case may be, issuable upon the exercise of the options
     referred to in clause (ii), (iv) shares of SPC Capital Stock issuable to
     participants the SPC Employee Stock Purchase Plan consistent with the terms
     thereof, and (v) shares of Allegro Common Stock pursuant to the terms
     hereof;
 
          (h) Cause, permit or propose any amendments to any charter document or
     Bylaw (or similar governing instruments of any subsidiaries), except to
     increase the size of the Board of Directors of Allegro to eleven directors;
 
          (i) Acquire or agree to acquire by merging or consolidating with, or
     by purchasing any equity interest in or a material portion of the assets
     of, or by any other manner, any business or any corporation, partnership
     interest, association or other business organization or division thereof,
     or otherwise acquire or agree to acquire any assets which are material,
     individually or in the aggregate, to the business of SPC or Allegro, as the
     case may be, or enter into any joint ventures, strategic partnerships or
     alliances, other than in the ordinary course of business consistent with
     past practice;
 
          (j) Sell, lease, license, encumber or otherwise dispose of any
     properties or assets which are material, individually or in the aggregate,
     to the business of SPC or Allegro, as the case may be, except in the
     ordinary course of business consistent with past practice;
 
          (k) Incur any indebtedness for borrowed money (other than ordinary
     course trade payables or pursuant to existing credit facilities in the
     ordinary course of business) or guarantee any such indebtedness or issue or
     sell any debt securities or warrants or rights to acquire debt securities
     of SPC or Allegro, as the case may be, or guarantee any debt securities of
     others;
 
          (l) Adopt or amend any employee benefit or stock purchase or option
     plan, or enter into any employment contract, pay any special bonus or
     special remuneration to any director or employee, or increase the salaries
     or wage rates of its officers or employees other than in the ordinary
     course of business, consistent with past practice;
<PAGE>
 
          (m) Pay, discharge or satisfy any claim, liability or obligation
     (absolute, accrued, asserted or unasserted, contingent or otherwise), other
     than the payment, discharge or satisfaction in the ordinary course of
     business;
 
          (n) Make any grant of exclusive rights to any third party;
 
          (o) Make any expenditure equal to or exceeding $15,000; or
 
          (p) Agree in writing or otherwise to take any of the actions described
     in Article 4 (a) through (o) above.
 
                                    ARTICLE V
 
                              ADDITIONAL AGREEMENTS
 
     5.1 Proxy  Statement/Prospectus;  Registration Statement; Other Filings. As
promptly as practicable  after the execution of this Agreement,  SPC and Allegro
will prepare and file with the SEC the Proxy  Statement and Allegro will prepare
and file with the SEC the  Registration  Statement in which the Proxy  Statement
will be included as a  prospectus.  Each of SPC and Allegro  will respond to any
comments  of the  SEC,  will  use its  best  efforts  to have  the  Registration
Statement declared effective under the Securities Act as promptly as practicable
after  such  filing  and will  cause  the  Proxy  Statement  to be mailed to its
stockholders at the earliest  practicable time. As promptly as practicable after
the date of this  Agreement,  SPC and  Allegro  will  prepare and file any other
filings  required  under  the  Exchange  Act,  the  Securities  Act or any other
Federal, foreign or state securities or Blue Sky laws relating to the Merger and
the  transactions  contemplated  by this Agreement (the "Other  Filings").  Each
party will notify the other party promptly upon the receipt of any comments from
the SEC or its  staff  and of any  request  by the SEC or its staff or any other
government   officials  for  amendments  or  supplements  to  the   Registration
Statement, the Proxy Statement or any Other Filing or for additional information
and will supply the other party with copies of all  correspondence  between such
party or any of its representatives,  on the one hand, and the SEC, or its staff
or any other  government  officials,  on the other  hand,  with  respect  to the
Registration Statement, the Proxy Statement, the Merger or any Other Filing. The
Proxy Statement, the Registration Statement and the Other Filings will comply in
all material respects with all applicable  requirements of law and the rules and
regulations promulgated thereunder.  Whenever any event occurs which is required
to be set  forth in an  amendment  or  supplement  to the Proxy  Statement,  the
Registration  Statement or any Other Filing, SPC or Allegro, as the case may be,
will promptly  inform the other party of such occurrence and cooperate in filing
with the SEC or its staff or any other government  officials,  and/or mailing to
stockholders  of SPC and  Allegro,  such  amendment  or  supplement.  The  Proxy
Statement will also include the recommendations of (i) the Board of Directors of
SPC in favor of approval of this  Agreement  (except to the extent  permitted by
Section 5.4) and (ii) the Board of Directors of Allegro in favor of the approval
of this  Agreement  (except that the Board of Directors of Allegro may withdraw,
modify or refrain from making such  recommendations to the extent that the Board
determines, in good faith, after discussion with outside legal counsel, that the
Board's fiduciary duties under applicable law require it to do so).
 
     5.2 Meetings of Stockholders. Promptly after the date hereof, SPC will take
all action  necessary in  accordance  with Delaware Law and its  Certificate  of
Incorporation and Bylaws to convene the SPC Stockholders'  Meeting to be held as
promptly as  practicable,  and in any event within 45 days after the declaration
of effectiveness of the Registration  Statement,  for the purpose of voting upon
this  Agreement.  SPC  will  consult  with  Allegro  and  use  its  commercially
reasonable efforts to hold the SPC Stockholders'  Meeting on the same day as the
Allegro Stockholders' Meeting. Promptly after the date hereof, Allegro will take
all action necessary in accordance with the Delaware General Corporation Law and
its Certificate of Incorporation and Bylaws to convene the Allegro Stockholders'
Meeting to be held as promptly as  practicable,  and in any event within 45 days
after the declaration of effectiveness of the  Registration  Statement,  for the
purpose of voting upon this  Agreement.  Allegro  will consult with SPC and will
use its  commercially  reasonable  efforts  to hold  the  Allegro  Stockholders'
Meeting on the same day as the SPC Stockholders'  Meeting.  Allegro and SPC will
each use its  commercially  reasonable  efforts to solicit from its stockholders
proxies  in favor of the  approval  of this  Agreement  and will  take all other
action  necessary or advisable to secure the vote or consent of their respective
stockholders  required by the Delaware  General  Corporation  Law to obtain such
approval (except to the extent permitted by Section 5.4).

<PAGE>
 
     5.3 Access to Information; Confidentiality.
 
     (a) Each party will afford the other party and its accountants, counsel and
other  representatives  reasonable  access during normal  business  hours to the
properties,  books,  records and  personnel of the other party during the period
prior to the Effective Time to obtain all  information  concerning the business,
including  the status of product  development  efforts,  properties,  results of
operations  and  personnel  of such  party,  as the other  party may  reasonably
request.  No information or knowledge obtained in any investigation  pursuant to
this  Section  5.3 will  affect or be deemed to  modify  any  representation  or
warranty contained herein or the conditions to the obligations of the parties to
consummate the Merger.
 
     (b) The parties acknowledge that Allegro and SPC have previously executed a
Confidentiality    Agreement   (the    "Confidentiality    Agreement"),    which
Confidentiality  Agreement  will continue in full force and effect in accordance
with its  terms,  except  as is  necessary  to  comply  with  the  terms of this
Agreement.
 
     5.4 No Solicitation by SPC.
 
     (a) From and after the date of this  Agreement  until  the  earlier  of the
Effective Time or termination of this Agreement  pursuant to its terms,  SPC and
its  subsidiaries  will  not,  and will  instruct  their  respective  directors,
officers, employees, representatives,  investment bankers, agents and affiliates
not to, directly or indirectly,  (i) solicit or knowingly  encourage  submission
of, any  proposals or offers by any person,  entity or group (other than Allegro
and its  affiliates,  agents and  representatives),  or (ii)  participate in any
discussions  or  negotiations  with,  or  disclose  any  non-public  information
concerning  SPC or any of its  subsidiaries  to,  or  afford  any  access to the
properties,  books or records of SPC or any of its subsidiaries to, or otherwise
assist or  facilitate,  or enter into any agreement or  understanding  with, any
person,  entity or group  (other  than  Allegro and its  affiliates,  agents and
representatives),  in connection with any  Acquisition  Proposal with respect to
SPC. For the purposes of this Agreement,  an "Acquisition Proposal" with respect
to  an  entity  means  any  proposal  or  offer  relating  to  (i)  any  merger,
consolidation,  sale of substantial assets or similar transactions involving the
entity  or any  subsidiaries  of the  entity  (other  than  sales of  assets  or
inventory  in the ordinary  course of business or  permitted  under the terms of
this  Agreement),  (ii) sale of 5% or more of the outstanding  shares of capital
stock of the entity (including without limitation by way of a tender offer or an
exchange offer),  (iii) the acquisition by any person of beneficial ownership or
a right to acquire beneficial  ownership of, or the formation of any "group" (as
defined under  Section  13(d) of the Exchange Act and the rules and  regulations
thereunder)  which  beneficially  owns,  or has the right to acquire  beneficial
ownership of, 5% or more of the then outstanding  shares of capital stock of the
entity  (except  for  acquisitions  for  passive  investment  purposes  only  in
circumstances  where the person or group  qualifies for and files a Schedule 13G
with respect thereto);  or (iv) any public  announcement of a proposal,  plan or
intention to do any of the  foregoing  or any  agreement to engage in any of the
foregoing.   SPC  will  immediately  cease  any  and  all  existing  activities,
discussions or negotiations with any parties  conducted  heretofore with respect
to any of the foregoing.  SPC will (i) notify Allegro as promptly as practicable
if any inquiry or proposal is made or any  information or access is requested in
writing in  connection  with an  Acquisition  Proposal or potential  Acquisition
Proposal and (ii) as promptly as practicable  notify Allegro of the  significant
terms and conditions of any such Acquisition Proposal.  In addition,  subject to
the  other  provisions  of this  Section  5.4,  from and  after the date of this
Agreement  until the  earlier  of the  Effective  Time and  termination  of this
Agreement  pursuant to its terms,  SPC and its  subsidiaries  will not, and will
instruct  their  respective  directors,  officers,  employees,  representatives,
investment bankers,  agents and affiliates not to, directly or indirectly,  make
or authorize any public statement,  recommendation or solicitation in support of
any  Acquisition  Proposal  made by any  person,  entity  or group  (other  than
Allegro);  provided,  however, that nothing herein shall prohibit SPC's Board of
Directors  from taking and  disclosing  to SPC's  stockholders  a position  with
respect to a tender offer  pursuant to Rules 14d-9 and 14e-2  promulgated  under
the Exchange Act.
 
     (b)  Notwithstanding  the  provisions of paragraph (a) above,  prior to the
approval of this Agreement by the  stockholders of SPC at the SPC  Stockholders'
Meeting,  SPC may, to the extent the Board of  Directors of SPC  determines,  in
good faith,  after  consultation  with outside legal  counsel,  that the Board's

<PAGE>

fiduciary  duties  under  applicable  law  require it to do so,  participate  in
discussions or negotiations  with, and, subject to the requirements of paragraph
(c),  below,  furnish  information  to any  person,  entity or group  after such
person,  entity or group has delivered to SPC in writing,  an  unsolicited  bona
fide Acquisition  Proposal which the Board of Directors of SPC in its good faith
reasonable  judgment   determines,   after  consultation  with  its  independent
financial  advisors,  would  result  in a  transaction  more  favorable  to  the
stockholders of SPC from a financial point of view than the Merger and for which
financing, to the extent required, is then committed or which, in the good faith
reasonable  judgment of the Board of  Directors of SPC (based upon the advice of
independent financial advisors), is reasonably capable of being financed by such
person,  entity or group and which is likely to be consummated (an "SPC Superior
Proposal"). In addition,  notwithstanding the provisions of paragraph (a) above,
in  connection  with a possible  Acquisition  Proposal,  SPC may refer any third
party to this  Section  5.4 or make a copy of this  Section 5.4  available  to a
third  party.  In the event  SPC  receives  an SPC  Superior  Proposal,  nothing
contained in this  Agreement  (but subject to the terms hereof) will prevent the
Board  of  Directors  of SPC  from  approving  such  SPC  Superior  Proposal  or
recommending  such SPC  Superior  Proposal to SPC's  stockholders,  if the Board
determines that such action is required by its fiduciary duties under applicable
law; in such case, the Board of Directors of SPC may withdraw, modify or refrain
from  making its  recommendation  concerning  the  approval  of this  Agreement;
provided,  however,  that SPC shall not accept or recommend to its stockholders,
or enter into any agreement concerning, an SPC Superior Proposal for a period of
not less than 48 hours after  Allegro's  receipt of a copy of such SPC  Superior
Proposal (or a description of the significant terms and conditions  thereof,  if
not in writing).
 
     (c) Notwithstanding anything to the contrary in paragraph (a), SPC will not
provide any  non-public  information  to a third party unless:  (x) SPC provides
such non-public  information  pursuant to a  nondisclosure  agreement with terms
regarding the protection of confidential  information at least as restrictive as
such terms in the Confidentiality Agreement; and (y) such non-public information
is the same information previously delivered to Allegro.
 
     5.5 Public Disclosure.  Allegro and SPC will consult with each other before
issuing any press release or otherwise  making any public statement with respect
to the Merger, this Agreement or an Alternative  Proposal and will not issue any
such press release or make any such public statement prior to such consultation,
except  as may be  required  by law or any  listing  agreement  with a  national
securities exchange or Nasdaq.
 
     5.6 Legal Requirements.  Each of Allegro,  Merger Sub and SPC will take all
reasonable  actions  necessary or desirable  to comply  promptly  with all legal
requirements  which may be imposed on them with respect to the  consummation  of
the  transactions  contemplated  by this  Agreement  (including  furnishing  all
information  required  in  connection  with  approvals  of or  filings  with any
Governmental  Entity,  and prompt resolution of any litigation  prompted hereby)
and will promptly  cooperate  with and furnish  information  to any party hereto
necessary in connection with any such  requirements  imposed upon any of them or
their  respective  subsidiaries  in  connection  with  the  consummation  of the
transactions  contemplated by this Agreement.  Allegro will use its commercially
reasonable  efforts to take such steps as may be  necessary  to comply  with the
securities  and blue sky laws of all  jurisdictions  which are applicable to the
issuance of Allegro Common Stock pursuant hereto.  SPC will use its commercially
reasonable  efforts to assist  Allegro as may be  necessary  to comply  with the
securities  and blue sky  laws of all  jurisdictions  which  are  applicable  in
connection with the issuance of Allegro Common Stock pursuant hereto.
 
     5.7 Third Party Consents. As soon as practicable following the date hereof,
Allegro and SPC will each use its commercially  reasonable efforts to obtain all
material  consents,  waivers and approvals under any of its or its subsidiaries'
agreements,  contracts, licenses or leases required to be obtained in connection
with the consummation of the transactions contemplated hereby.
 
     5.8 FIRPTA. At or prior to the Closing, SPC, if requested by Allegro, shall
deliver  to the IRS a notice  that  the SPC  Capital  Stock is not a "U.S.  Real
Property  Interest"  as  defined  and in  accordance  with the  requirements  of
Treasury Regulation Section 1.897-2(h)(2).
 
     5.9  Notification  of  Certain  Matters.  Allegro  and Merger Sub will give
prompt  notice  to SPC,  and SPC will give  prompt  notice  to  Allegro,  of the
occurrence,  or failure to occur, of any event,  which  occurrence or failure to


<PAGE>

occur would be  reasonably  likely to cause (a) any  representation  or warranty
contained in this  Agreement to be untrue or inaccurate in any material  respect
at any time from the date of this  Agreement to the  Effective  Time, or (b) any
material failure of Allegro and Merger Sub or SPC, as the case may be, or of any
officer,  director,  employee  or agent  thereof,  to comply with or satisfy any
covenant,  condition or  agreement to be complied  with or satisfied by it under
this Agreement.  Notwithstanding  the above, the delivery of any notice pursuant
to this  section  will not limit or  otherwise  affect  the  remedies  available
hereunder to the party receiving such notice.
 
     5.10 Best Efforts and Further Assurances.  Subject to the respective rights
and obligations of Allegro and SPC under this Agreement,  each of the parties to
this  Agreement will use its best efforts to effectuate the Merger and the other
transactions  contemplated  hereby and to fulfill and cause to be fulfilled  the
conditions to closing under this Agreement. Each party hereto, at the reasonable
request of another party hereto, will execute and deliver such other instruments
and do and perform  such other acts and things as may be  necessary or desirable
for effecting  completely  the  consummation  of the  transactions  contemplated
hereby.
 
     5.11 Stock Options; Employee Stock Purchase Plan.
 
     (a) At the Effective  Time, each  outstanding  option to purchase shares of
SPC Capital Stock (each an "SPC Stock Option") under the SPC Stock Option Plans,
whether or not exercisable, will be assumed by Allegro. Each SPC Stock Option so
assumed by Allegro under this  Agreement  will continue to have,  and be subject
to, the same terms and  conditions  set forth in the applicable SPC Stock Option
Plan immediately prior to the Effective Time (including, without limitation, any
repurchase  rights),  except that (i) each SPC Stock Option will be  exercisable
(or will become  exercisable  in  accordance  with its terms) for that number of
whole  shares of  Allegro  Common  Stock  equal to the  product of the number of
shares of SPC Capital  Stock that were  issuable upon exercise of such SPC Stock
Option immediately prior to the Effective Time multiplied by the Exchange Ratio,
rounded down to the nearest whole number of shares of Allegro Common Stock,  and
(ii) the per  share  exercise  price  for the  shares of  Allegro  Common  Stock
issuable  upon  exercise of such  assumed SPC Stock  Option will be equal to the
quotient  determined  by dividing  the  exercise  price per share of SPC Capital
Stock at which such SPC Stock Option was  exercisable  immediately  prior to the
Effective  Time by the  Exchange  Ratio,  rounded up to the nearest  whole cent.
After the Effective  Time,  Allegro will issue to each holder of an  outstanding
SPC Stock Option a notice describing the foregoing  assumption of such SPC Stock
Option by Allegro.
 
     (b) It is the  intention of the parties that SPC Stock  Options  assumed by
Allegro  qualify  following  the  Effective  Time as incentive  stock options as
defined in Section 422 of the Code to the extent SPC Stock Options  qualified as
incentive stock options immediately prior to the Effective Time.
 
     (c) Allegro  will  reserve  sufficient  shares of Allegro  Common Stock for
issuance under Section 5.11(a) and under Section 1.6(c) hereof.
 
     5.12 Form S-8. Allegro agrees to file a registration  statement on Form S-8
for the shares of Allegro  Common  Stock  issuable  with  respect to assumed SPC
Stock Options no later than ten (10) business days after the Closing Date.
 
     5.13 Indemnification and Insurance.
 
     (a) From and after the  Effective  Time,  the  Surviving  Corporation  will
fulfill  and  honor in all  respects  the  obligations  of SPC  pursuant  to any
indemnification  agreements  between SPC and its directors and officers existing
prior to the date hereof.  The  Certificate of  Incorporation  and Bylaws of the
Surviving  Corporation will contain  provisions with respect to  indemnification
and elimination of liability for monetary damages not less favorable to officers
and directors to those set forth in the Certificate of Incorporation  and Bylaws
of SPC, which provisions will not be amended,  repealed or otherwise modified in
a manner  adverse to officers and  directors  for a period of six years from the
Effective Time in any manner that would adversely  affect the rights  thereunder
of individuals who, at the Effective Time, were directors,  officers,  employees
or agents of SPC, unless such modification is required by law.
 

<PAGE>

     (b) After the Effective Time the Surviving Corporation will, to the fullest
extent  permitted  under  applicable  law or under the  Surviving  Corporation's
Certificate  of  Incorporation  or Bylaws,  indemnify  and hold  harmless,  each
present  and  former  director  or  officer  of SPC  or any of its  subsidiaries
(collectively,   the  "Indemnified  Parties")  against  any  costs  or  expenses
(including  attorneys'  fees),   judgments,   fines,  losses,  claims,  damages,
liabilities and amounts paid in settlement in connection with any claim, action,
suit, proceeding or investigation,  whether civil,  criminal,  administrative or
investigative,  to the  extent  arising  out of or  pertaining  to any action or
omission  in his or her  capacity as a director or officer of SPC arising out of
or pertaining to the transactions contemplated by this Agreement for a period of
six years after the date hereof. In the event of any such claim,  action,  suit,
proceeding  or  investigation  (whether  arising  before or after the  Effective
Time), (i) any counsel retained by the Indemnified  Parties for any period after
the Effective Time will be reasonably  satisfactory to the Surviving Corporation
and Allegro,  (ii) after the Effective Time, the Surviving  Corporation will pay
the  reasonable  fees and expenses of such counsel,  promptly  after  statements
therefor are received and (iii) the Surviving  Corporation will cooperate in the
defense of any such matter;  provided,  however,  that the Surviving Corporation
will not be liable for any  settlement  effected  without  its  written  consent
(which consent will not be unreasonably withheld); and provided,  further, that,
in the event that any claim or claims for  indemnification  are asserted or made
within such six-year  period,  all rights to  indemnification  in respect of any
such claim or claims will  continue  until the  disposition  of any and all such
claims.  The  Indemnified  Parties as a group may  retain  only one law firm (in
addition to local  counsel) to represent  them with respect to any single action
unless there is, under applicable standards of professional  conduct, a conflict
on any  significant  issue between the positions of any two or more  Indemnified
Parties.
 
     (c) Allegro shall maintain  through  September 3, 1997 the current policies
of directors' and officers' liability insurance maintained by SPC. The Surviving
Corporation shall pay all retentions and deductibles  payable by any Indemnified
Party with  respect to such  policies;  provided,  that if and to the extent the
Surviving   Corporation  has  insufficient  cash  to  pay  such  retentions  and
deductibles in full, the remaining amounts payable shall be paid by Allegro.
 
     (d)  Promptly   after  the  Effective   Time,   Allegro  shall  enter  into
indemnification  agreements  with  directors  and  officers  of SPC  who  become
directors  or  officers  of  Allegro  or of  the  Surviving  Corporation,  which
agreements shall be  substantially  identical to those which Allegro has entered
with its current officers and directors.
 
     (e) This Section 5.13 will survive any  termination  of this  Agreement and
the  consummation  of the Merger at the  Effective  Time, is intended to benefit
SPC, the Surviving  Corporation and the Indemnified Parties, and will be binding
on all  successors and assigns of the Surviving  Corporation.  If Allegro or the
Surviving  Corporation  or any of their  respective  successors  or assigns  (i)
consolidates with or merges into any other person or entity and shall not be the
continuing or surviving person of such consolidation or merger or (ii) transfers
all or  substantially  all of its properties and assets to any person or entity,
then  and in each  such  case,  proper  provision  shall  be  made so that  such
successors or assigns of Allegro or the Surviving  Corporation,  as the case may
be, shall assume the obligations set forth in this Section 5.13.
 
     5.14   Tax-Free   Reorganization.   Allegro  and  SPC  will  each  use  its
commercially  reasonable  efforts  to  cause  the  Merger  to  be  treated  as a
reorganization  within the meaning of Section  368 of the Code.  Allegro and SPC
will each make available to the other party and their  respective  legal counsel
copies of all returns requested by the other party.
 
     5.15 NASDAQ Listing.  Allegro agrees to apply for authorization for listing
on the Nasdaq SmallCap  Market the shares of Allegro Common Stock issuable,  and
those required to be reserved for issuance,  in connection with the Merger, upon
official notice of issuance, and will use its commercially reasonable efforts to
have its Common  Stock  authorized  for  listing on the Nasdaq  National  Market
System as soon as reasonably practicable.
 

<PAGE>

     5.16 SPC Affiliate  Agreement.  Set forth on the SPC Schedules is a list of
those persons who may be deemed to be, in SPC's reasonable judgment,  affiliates
of SPC within the meaning of Rule 145  promulgated  under the Securities Act (an
"SPC  Affiliate").  SPC will provide Allegro with such information and documents
as Allegro reasonably requests for purposes of reviewing such list. SPC will use
its best  efforts to deliver or cause to be  delivered  to Allegro  prior to the
Closing  Date  from  each SPC  Affiliate  an  executed  affiliate  agreement  in
substantially  the  form  attached  hereto  as  Exhibit  A (the  "SPC  Affiliate
Agreement"),  each of which will be in full force and effect as of the Effective
Time. Allegro will be entitled to place appropriate  legends on the certificates
evidencing any Allegro Common Stock to be received by an SPC Affiliate  pursuant
to  the  terms  of  this  Agreement,  and to  issue  appropriate  stop  transfer
instructions to the transfer agent for the Allegro Common Stock, consistent with
the terms of the SPC Affiliate Agreement.
 
     5.17 Board of Directors of Allegro.  The Board of Directors of Allegro will
take  all  actions  necessary  to  cause  the  Board of  Directors  of  Allegro,
immediately after the Effective Time, to consist of eleven persons, nine of whom
shall have served on the Board of Directors of Allegro  immediately prior to the
Effective  Time and two of whom shall have served on the Board of  Directors  of
SPC immediately  prior to the Effective Time (one of whom shall be Fred Gibbons,
in Class III, and one of whom shall be designated by the SPC Board of Directors,
and is currently  expected to be Miriam  Frazer,  in Class II). If, prior to the
Effective  Time, any of the SPC or Allegro  designees shall decline or be unable
to serve as an SPC or Allegro  director,  SPC (if such person was  designated by
SPC) or Allegro  (if such person was  designated  by  Allegro)  shall  designate
another person to serve in such person's stead, which person shall be reasonably
acceptable to the other party.
 
     5.18 Loan  Facility.  From the date hereof  through the  Effective  Date or
earlier termination of the Agreement,  SPC shall, upon request by Allegro,  loan
up to  $1,000,000  to  Allegro.  SPC  shall  not be  required  to loan more than
one-third of the maximum loan amount in any 30-day  period,  and the proceeds of
all loans shall be used only for working capital  purposes;  provided,  however,
that no such loan shall be  required  to be made  unless and until the  fairness
opinions  referred  to in Sections  6.2(e) and 6.3(f) have been  received or the
condition  relating  thereto  waived.  Any such  loan  shall be  evidenced  by a
promissory note with the following terms:
 
          (a) maturity on the tenth anniversary of the date of any loan;
 
          (b) in the event that this Agreement is terminated by Allegro, the
     note shall be converted into shares of Common Stock of Allegro at the Loan
     Conversion Price (as defined below);
 
          (c) in the event this Agreement is terminated by SPC, the note (less
     any amount payable by SPC to Allegro pursuant to Section 7.3(b) of this
     Agreement) shall be converted into shares of Common Stock of Allegro at the
     Loan Conversion Price; provided, however, that in the event that such
     termination shall result in a fee payable by Allegro to SPC pursuant to
     Section 7.3(c) of this Agreement, only one-half of the note shall be so
     converted and the remaining one-half shall be repayable at the same time
     and in the same manner as the fee payable pursuant to Section 7;
 
          (d) the note shall bear interest at a rate per annum equal to the
     prime rate plus 2%.
 
     As used  herein,  the term "Loan  Conversion  Price"  shall mean 90% of the
average of the last reported sale prices of the Allegro Common Stock for the ten
trading  days  ending on the day  immediately  prior to the date of  termination
leading to conversion of the loan(s).
 
     5.19  Fairness  Opinions.  Each of SPC and  Allegro  shall use  their  best
efforts to obtain the  fairness  opinions  referred  to in  Sections  6.2(e) and
6.3(e), respectively.
 
     5.20 SPC  Employee  Benefits.  Subject to being able to do so  consistently
with  applicable  laws,   after  the  Effective  Date,   Allegro  will  use  its
commercially reasonable efforts to cause the Surviving Corporation to provide to
the  employees of SPC employee  benefits  comparable to those under the existing
SPC plans generally available to SPC employees.
 

<PAGE>

                                   ARTICLE VI
 
                            CONDITIONS TO THE MERGER
 
     6.1  Conditions  to  Obligations  of Each Party to Effect the  Merger.  The
respective  obligations  of each  party to this  Agreement  to effect the Merger
shall be subject to the  satisfaction  at or prior to the Effective  Time of the
following conditions:
 
          (a) Stockholder Approval.  This Agreement shall have been approved
     and adopted, and the Merger shall have been duly approved, by the 
     requisite vote under applicable law by the stockholders of SPC and by the
     stockholders of Allegro.

          (b) Registration Statement Effective.  The SEC shall have declared the
     Registration Statement effective. No stop order suspending the
     effectiveness of the Registration Statement or any part thereof shall have
     been issued and no proceeding for that purpose, and no similar proceeding
     in respect of the Proxy Statement, shall have been initiated or threatened
     in writing by the SEC.
 
          (c) No Order.  No Governmental Entity shall have enacted, issued,
     promulgated, enforced or entered any statute, rule, regulation, executive
     order, decree, injunction or other order (whether temporary, preliminary or
     permanent) which is in effect and which has the effect of making the Merger
     illegal or otherwise prohibiting consummation of the Merger.
 
          (d) Nasdaq Listing.  The shares of Allegro Common Stock issuable to
     stockholders of SPC pursuant to this Agreement and such other shares
     required to be reserved for issuance in connection with the Merger shall
     have been authorized for listing on the Nasdaq SmallCap upon official
     notice of issuance.
 
     6.2 Additional  Conditions to Obligations of SPC. The obligations of SPC to
consummate  and  effect the Merger  shall be subject to the  satisfaction  at or
prior to the Effective  Time of each of the following  conditions,  any of which
may be waived, in writing, exclusively by SPC:
 
          (a) Representations and Warranties.  The representations and
     warranties of Allegro and Merger Sub contained in this Agreement shall be
     true and correct on and as of the Effective Time, except for changes
     contemplated by this Agreement and except for those representations and
     warranties which address matters only as of a particular date (which shall
     remain true and correct as of such particular date), with the same force
     and effect as if made on and as of the Effective time, except, in all
     such cases where the failure to be so true and correct, would not have a
     Material Adverse Effect on Allegro; and SPC shall have received a 
     certificate to such effect signed on behalf of Allegro by the Chief
     Financial Officer of Allegro;
 
          (b) Agreements and Covenants.  Allegro and Merger Sub shall have
     performed or complied in all material respects with all agreements and
     covenants required by this Agreement to be performed or complied with by
     them on or prior to the Effective Time, and SPC shall have received a
     certificate to such effect signed on behalf of Allegro by the Chief
     Financial Officer of Allegro;
 
          (c) Material Adverse Effect.  No Material Adverse Effect with respect
     to Allegro shall have occurred since the date of this Agreement; and
 
          (d) Legal Opinion.  SPC shall have received a legal opinion from Blau,
     Kramer, Wactlar & Lieberman, P.C., counsel to Allegro, in a form reasonably
     acceptable to SPC.
 
          (e) Fairness Opinion.  SPC shall have received a written opinion from
     Unterberg Harris or another investment banking firm by not later than
     October 11, 1996, to the effect that as of the date hereof, the Exchange
     Ratio is fair to SPC's stockholders from a financial point of view, and
     shall have delivered to Allegro by not later than such date a copy of such
     opinion.
 

<PAGE>

     6.3 Additional Conditions to the Obligations of Allegro and Merger Sub. The
obligations  of Allegro and Merger Sub to consummate and effect the Merger shall
be subject to the  satisfaction at or prior to the Effective Time of each of the
following  conditions,  any of which may be waived,  in writing,  exclusively by
Allegro:
 
          (a) Representations and Warranties.  The representations and
     warranties of SPC contained in this Agreement shall be true and correct on
     and as of the Effective Time, except for changes contemplated by this
     Agreement and except for those representations and warranties which address
     matters only as of a particular date (which shall remain true and correct
     as of such particular date), with the same force and effect as if made on
     and as of the Effective Time, except, in all such cases where the failure
     to be so true and correct, would not have a Material Adverse Effect on SPC;
     and Allegro and Merger Sub shall have received a certificate to such effect
     signed on behalf of SPC by the Chief Financial Officer of SPC;
 
          (b) Agreements and Covenants.  SPC shall have performed or complied in
     all material respects with all agreements and covenants required by this
     Agreement to be performed or complied with by it on or prior to the
     Effective Time, and the Allegro shall have received a certificate to such
     effect signed on behalf of SPC by the Chief Financial Officer of SPC;
 
          (c) Material Adverse Effect.  No Material Adverse Effect with respect
     to SPC shall have occurred since the date of this Agreement;
 
          (d) Legal Opinion.  Allegro shall have received a legal opinion from
     Wilson Sonsini Goodrich & Rosati, counsel to SPC, in a form reasonably
     acceptable to Allegro.
 
          (e) Fairness Opinion.  Allegro has received a written opinion from
     Frost Capital Partners, Inc. or another investment banking firm by not
     later than October 11, 1996 to the effect that as of the date hereof, the
     Merger is fair to Allegro's stockholders from a financial point of view,
     and shall have delivered to SPC a copy of such opinion by not later than
     such date.
 
          (f) Termination of SPC Shareholder Rights Plan.  SPC's Shareholder
     Rights Plan shall either have been terminated or its operation waived with
     regard to the transaction contemplated hereby.
 
                                   ARTICLE VII
 
                        TERMINATION, AMENDMENT AND WAIVER
 
     7.1 Termination.  This Agreement may be terminated at any time prior to the
Effective Time of the Merger,  whether before or after approval of the Merger by
the stockholders of Allegro and SPC:
 
          (a) by mutual written consent duly authorized by the Boards of
     Directors of Allegro and SPC;
 
          (b) by either SPC or Allegro if the Merger shall not have been
     consummated by February 15, 1997; provided, however, that the right to
     terminate this Agreement under this Section 7.1(b) shall not be available
     to any party whose action or failure to act has been a principal cause of
     or resulted in the failure of the Merger to occur on or before such date
     and such action or failure to act constitutes a breach of this Agreement;
 
          (c) by either SPC or Allegro if a court of competent jurisdiction or
     governmental, regulatory or administrative agency or commission shall have
     issued an order, decree or ruling or taken any other action (an "Order"),
     in any case having the effect of permanently restraining, enjoining or
     otherwise prohibiting the Merger, which order, decree or ruling is final
     and nonappealable;
 
          (d) by either SPC or Allegro if the required approvals of the
     stockholders of SPC and Allegro contemplated by this Agreement shall not
     have been obtained by reason of the failure to obtain the required vote
     upon a vote taken at a meeting of stockholders duly convened therefor or 
     at any adjournment thereof (provided that the right to terminate this
     Agreement under this Section 7.1(d) shall not be available to any party
     where the failure to obtain stockholder approval of such party shall have
     been caused by the action or failure to act of such party in breach of this
     Agreement);
 
<PAGE>

          (e) by either SPC or Allegro, if SPC shall have accepted an SPC
     Superior Proposal or by Allegro if the SPC Board of Directors recommends
     an SPC Superior Proposal to the stockholders of SPC;
 
          (f) by Allegro, if the Board of Directors of SPC shall have withheld,
     withdrawn or modified in a manner adverse to Allegro its recommendation in
     favor of approving the issuance of the shares of Allegro Common Stock by
     virtue of the Merger;
 
          (g) by SPC, if the Board of Directors of Allegro shall have withheld,
     withdrawn or modified in a manner adverse to SPC its recommendation in
     favor of the Merger;
 
          (h) by SPC, upon a material breach of any representation, warranty,
     covenant or agreement on the part of Allegro set forth in this Agreement,
     or if any representation or warranty of Allegro shall have become untrue in
     any material respect, in either case such that the conditions set forth in
     Section 6.2(a) or Section 6.2(b) would not be satisfied as of the time of
     such breach or as of the time such representation or warranty shall have
     become untrue, provided that if such inaccuracy in Allegro's
     representations and warranties or breach by Allegro is curable by Allegro
     through the exercise of its commercially reasonable efforts within fifteen
     (15) days of the time such representation or warranty shall have become
     untrue or such breach, then SPC may not terminate this Agreement under this
     Section 7.1(h) during such fifteen-day period provided Allegro continues to
     exercise such commercially reasonable efforts;
 
          (i) by Allegro, upon a material breach of any representation,
     warranty, covenant or agreement on the part of SPC set forth in this
     Agreement, or if any representation or warranty of SPC shall have become
     untrue in any material respect, in either case such that the conditions set
     forth in Section 6.3(a) or Section 6.3(b) would not be satisfied as of the
     time of such breach or as of the time such representation or warranty shall
     have become untrue, provided, that if such inaccuracy in the Company's
     representations and warranties or breach by SPC is curable by SPC through
     the exercise of its commercially reasonable efforts within fifteen (15)
     days of the time such representation or warranty shall have become untrue
     or such breach, then Allegro may not terminate this Agreement under this
     Section 7.1(i) during such fifteen-day period provided SPC continues to
     exercise such commercially reasonable efforts;
 
          (j) by SPC, if there shall have occurred any Material Adverse Effect
     with respect to Allegro since the date of this Agreement;
 
          (k) by Allegro, if there shall have occurred any Material Adverse
     Effect with respect to SPC since the date of this Agreement;
 
          (l) by SPC, if the condition specified in Section 6.2(e) has not been
     satisfied by October 11, 1996; or
 
          (m) by Allegro, if the condition specified in Section 6.3(e) has not
     been satisfied by October 11, 1996.
 
     7.2 Notice of Termination; Effect of Termination.
 
     (a) Subject to Sections  7.2(b) and (c), any  termination of this Agreement
under  Section  7.1 above will be  effective  immediately  upon the  delivery of
written  notice of the  terminating  party to the other parties  hereto.  In the
event of the  termination  of this  Agreement as provided in Section  7.1,  this
Agreement  shall be of no further  force or  effect,  except (i) as set forth in
this Section 7.2, Section 7.3 and Article 8 (miscellaneous), each of which shall
survive the termination of this Agreement, and (ii) nothing herein shall relieve
any  party  from  liability  for  any  willful  breach  of  this  Agreement.  No
termination  of this  Agreement  shall  affect the  obligations  of the  parties
contained  in the  Confidentiality  Agreement,  all of which  obligations  shall
survive termination of this Agreement in accordance with their terms.
 
     (b) Any termination of this Agreement by SPC pursuant to Sections 7.1(d) or
7.1(e)  hereof shall be of no force or effect  unless prior to such  termination
SPC shall have paid to Allegro any amounts payable pursuant to Section 7.3(b).
 
<PAGE>

     (c) Any  termination  of this  Agreement  by Allegro  pursuant  to Sections
7.1(d) or 7.1(g)  hereof  shall be of no force or  effect  unless  prior to such
termination  Allegro  shall have paid to SPC any  amounts  payable  pursuant  to
Section 7.3(c).
 
     7.3 Fees and Expenses.
 
     (a) Except as set forth in this Section 7.3, all fees and expenses incurred
in connection with this Agreement and the transactions contemplated hereby shall
be paid by the party  incurring  such  expenses,  whether  or not the  Merger is
consummated;  provided,  however,  that Allegro and SPC shall share  equally all
fees and expenses,  other than reasonable  attorneys' and  accountants  fees and
expenses, incurred in relation to the printing and filing of the Proxy Statement
(including  any  preliminary  materials  related  thereto) and the  Registration
Statement  (including  financial  statements and exhibits) and any amendments or
supplements thereto.
 
     (b) SPC shall  immediately  make  payment to Allegro  (by wire  transfer or
certified or cashiers  check) of (x)  $1,000,000 (i) in the event SPC shall have
accepted an SPC Superior Proposal or if the SPC Board of Directors recommends an
SPC Superior  Proposal to the stockholders of SPC, or (ii) in the event the vote
of the  stockholders  of SPC  contemplated by this Agreement shall not have been
obtained by reason of the failure to obtain the required  vote upon a vote taken
at a meeting  of  stockholders  duly  convened  therefor  or at any  adjournment
thereof (an "SPC Negative  Vote") if prior to such SPC Negative Vote there shall
have occurred an Acquisition  Proposal with respect to SPC which shall have been
publicly  disclosed and not withdrawn;  or (iii) in the event of an SPC Negative
Vote if prior to such SPC Negative Vote the Board of Directors of SPC shall have
withheld,   withdrawn   or  modified   in  a  manner   adverse  to  Allegro  its
recommendation in favor of the Merger or (y) $750,000 in the event of (i) an SPC
Negative  Vote if SPC shall not be  required to make  payment of the  $1,000,000
required  by clause  (x) above or (ii) a  failure  to  perform  or  observe  any
covenant of SPC contained herein.
 
     (c) Allegro  shall  immediately  make  payment to SPC (by wire  transfer or
certified or cashiers check) of $750,000 in the event of (i) an Allegro Negative
Vote or (ii) a failure to perform or observe any  covenant of Allegro  contained
herein.
 
     (d) Payment of the fees described in Section 7.3(b) and (c) above shall not
be in lieu of damages incurred in the event of breach of this Agreement.
 
     7.4 Amendment.  Subject to applicable law, this Agreement may be amended by
the parties  hereto at any time by execution of an instrument in writing  signed
on behalf of each of the parties hereto.
 
     7.5  Extension;  Waiver.  At any time prior to the Effective Time any party
hereto  may,  to the  extent  legally  allowed,  (i)  extend  the  time  for the
performance of any of the obligations or other acts of the other parties hereto,
(ii) waive any inaccuracies in the  representations  and warranties made to such
party contained  herein or in any document  delivered  pursuant hereto and (iii)
waive  compliance  with any of the  agreements or conditions  for the benefit of
such party contained herein.  Any agreement on the part of a party hereto to any
such  extension or waiver shall be valid only if set forth in an  instrument  in
writing signed on behalf of such party.
 
                                  ARTICLE VIII
 
                               GENERAL PROVISIONS
 
     8.1 Non-Survival of Representations and Warranties. The representations and
warranties  of SPC,  Allegro and Merger Sub  contained in this  Agreement  shall
terminate at the  Effective  Time,  and only the  covenants  that by their terms
survive the Effective Time shall survive the Effective Time.
 
     8.2 Notices.  All notices and other  communications  hereunder  shall be in
writing  and shall be deemed  given if  delivered  personally  or by  commercial
delivery service, or sent via telecopy (receipt confirmed) to the parties at the
following  addresses or telecopy  numbers (or at such other  address or telecopy
numbers for a party as shall be specified by like notice):
 
 
<PAGE>

         (a) if to Allegro or Merger Sub, to:
 
          Allegro New Media, Inc.
          3 Oak Road
          Fairfield, New Jersey 07004
          Attention: Barry A. Cinnamon
            President
          Telephone No.: (201) 808-1992
          Telecopy No.: (201) 808-2645
 
          with a copy to:
 
          Blau, Kramer, Wactlar & Lieberman, P.C.
          100 Jericho Quadrangle
          Jericho, New York 11753
          Attention: Neil M. Kaufman, Esq.
          Telephone No.: (516) 822-4820
          Telecopy No.: (516) 822-4824
 
        (b) if to SPC, to:
 
           Software Publishing Corporation
           111 North Market Street
           San Jose, CA 95113
           Attention: Miriam Frazer
           Telephone No.: (408) 537-3000
           Telecopy No.: (408) 537-3506
 
           with a copy to:
 
          Wilson Sonsini Goodrich & Rosati, Professional Corporation
          650 Page Mill Road
          Palo Alto, CA 94304-1050
          Attention: Herbert Fockler, Esq.
          Telephone No.: (415) 493-9300
          Telecopy No.: (415) 493-6811
 
     8.3 Interpretation; Knowledge.
 
          (a) When a reference is made in this Agreement to Exhibits, such
     reference shall be to an Exhibit to this Agreement unless otherwise
     indicated. The words "include," "includes" and "including" when used herein
     shall be deemed in each case to be followed by the words "without
     limitation." The table of contents and headings contained in this Agreement
     are for reference purposes only and shall not affect in any way the meaning
     or interpretation of this Agreement. When reference is made herein to "the
     business of" an entity, such reference shall be deemed to include the
     business of all direct and indirect subsidiaries of such entity. Reference
     to the subsidiaries of an entity shall be deemed to include all direct and
     indirect subsidiaries of such entity.
 
          (b) For purposes of this Agreement, the term "knowledge" means, with
     respect to any matter in question, that the executive officers of SPC or
     Allegro, as the case may be, have actual knowledge of such matter.
 
     8.4   Counterparts.   This  Agreement  may  be  executed  in  one  or  more
counterparts,  all of which shall be considered  one and the same  agreement and
shall become effective when one or more counterparts have been signed by each of
the parties and  delivered  to the other  party,  it being  understood  that all
parties need not sign the same counterpart.
 
     8.5 Entire Agreement.  This Agreement and the documents and instruments and
other  agreements  among the parties  hereto as  contemplated  by or referred to
herein,  including SPC Schedules and the Allegro  Schedules (a)  constitute  the
entire agreement among the parties with respect to the subject matter hereof and
supersede all prior agreements and understandings,  both written and oral, among
the parties with respect to the subject matter hereof,  it being understood that
the Confidentiality  Agreement shall continue in full force and effect until the
Closing and shall survive any  termination  of this  Agreement;  and (b) are not
intended  to confer  upon any other  person  any rights or  remedies  hereunder,
except as set forth herein.
 

<PAGE>

     8.6 Severability.  In the event that any provision of this Agreement or the
application thereof, becomes or is declared by a court of competent jurisdiction
to be illegal,  void or  unenforceable,  the  remainder of this  Agreement  will
continue in full force and effect and the application of such provision to other
persons or  circumstances  will be  interpreted  so as  reasonably to effect the
intent of the parties hereto.  The parties further agree to replace such void or
unenforceable provision of this Agreement with a valid and enforceable provision
that will achieve,  to the extent  possible,  the  economic,  business and other
purposes of such void or unenforceable provision.
 
     8.7 Other  Remedies;  Specific  Performance.  Except as otherwise  provided
herein,  any and all remedies  herein  expressly  conferred upon a party will be
deemed  cumulative with and not exclusive of any other remedy conferred  hereby,
or by law or equity  upon such  party,  and the  exercise  by a party of any one
remedy will not preclude the exercise of any other  remedy.  The parties  hereto
agree  that  irreparable  damage  would  occur  in  the  event  that  any of the
provisions  of this  Agreement  were not  performed  in  accordance  with  their
specific terms or were  otherwise  breached.  It is accordingly  agreed that the
parties shall be entitled to an injunction or injunctions to prevent breaches of
this Agreement and to enforce  specifically  the terms and provisions  hereof in
any court of the United States or any state having  jurisdiction,  this being in
addition to any other remedy to which they are entitled at law or in equity.
 
     8.8  Governing  Law. This  Agreement  shall be governed by and construed in
accordance  with the laws of the State of Delaware,  regardless of the laws that
might otherwise govern under applicable  principles of conflicts of law thereof.
Each of the parties hereto irrevocably consents to the exclusive jurisdiction of
any state or federal court within the State of Delaware,  in connection with any
matter based upon or arising out of this  Agreement or the matters  contemplated
herein,  agrees that process may be served upon them in any manner authorized by
the laws of the State of Delaware for such persons and waives and  covenants not
to  assert  or plead any  objection  which  they  might  otherwise  have to such
jurisdiction and such process.
 
     8.9 Rules of  Construction.  The parties  hereto  agree that they have been
represented  by counsel during the  negotiation  and execution of this Agreement
and, therefore, waive the application of any law, regulation, holding or rule of
construction  providing that  ambiguities in an agreement or other document will
be construed against the party drafting such agreement or document.

     8.10  Assignment.  No party may assign either this  Agreement or any of its
rights,  interests,  or obligations hereunder without the prior written approval
of the other parties.
 
     IN WITNESS WHEREOF, Allegro, Merger Sub, and SPC have caused this Agreement
to be signed by themselves or their duly authorized respective officers,  all as
of the date first written above.
 
                                       ALLEGRO NEW MEDIA, INC.

                                       By: /s/       BARRY CINNAMON
                                         ------------------------------------
                                       Name: Barry Cinnamon
                                       Title: Chairman

                                       SOFTWARE PUBLISHING CORPORATION

                                       By: /s/        FRED GIBBONS
                                         ------------------------------------
                                       Name: Fred Gibbons
                                       Title: Chairman

                                       By: /s/        MIRIAM FRAZER
                                         ------------------------------------
                                       Name: Miriam Frazer
                                       Title: V.P. Finance and Chief Financial
                                       Officer

                                       SPC ACQUISITION CORPORATION

                                       By: /s/       BARRY CINNAMON
                                         ------------------------------------
                                       Name: Barry Cinnamon
                                       Title: President