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                                                                     EXHIBIT 4.9



                           5% SECURED PROMISSORY NOTE


$1,200,000.00                                                   January 18, 2002


               FOR VALUE RECEIVED, e.Digital Corporation, a Delaware corporation
(the "Maker"), with its primary offices located at 13114 Evening Creek Drive
South, San Diego, California 92128, promises to pay to the order of Immanuel
Kant International Limited, or its registered assigns (the "Payee"), upon the
terms set forth below, the principal sum of One Million Two Hundred Thousand
Dollars ($1,200,000.00) plus interest on the unpaid principal sum outstanding at
the rate of 5% per annum.

1. Payments. (a) The full amount of principal and accrued interest under this
Note shall be due on April 18, 2002 (the "Maturity Date"), unless due earlier in
accordance with the terms of this Note.

               (b) Maker may prepay the full (but not less than full) principal
sum and interest under this Note until the Maturity Date or such earlier time as
the principal sum and interest become due in accordance with the terms of this
Note. Any such prepayment shall be in cash in the amount of $1,320,000 on
account of principal, plus all interest accrued through the date of prepayment.

2. Secured Obligation. Maker's obligations under this Note are secured pursuant
to the Security Agreement, dated January 18, 2002, entered into among Maker,
e.Digital Corporation, a California corporation and a wholly owned subsidiary of
Maker (the "Subsidiary"), and the Payee (the "Security Agreement"), and the
Intellectual Property Security Agreement, dated January 18, 2002, entered into
among Maker, Subsidiary and the Payee, the "IP Security Agreement", and
collectively with the Security Agreement, the "Security Agreements").

3.      Events of Default.

       (a) "Event of Default", wherever used herein, means any one of the
following events (whatever the reason and whether it shall be voluntary or
involuntary or effected by operation of law or pursuant to any judgment, decree
or order of any court, or any order, rule or regulation of any administrative or
governmental body):

     (i) any default in the payment of the principal of, or the interest on,
this Note, as and when the same shall become due and payable;

     (ii) Maker shall fail to observe or perform any obligation or shall breach
any term or provision of this Note and such failure or breach shall not have
been remedied within five days after the date on which notice of such failure or
breach shall have been delivered;

     (iii) Maker or Subsidiary shall fail to observe or perform any of their
respective Obligations (as defined in the Security Agreements) or any other
covenant, agreement, representation or warranty

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contained in, or otherwise commit any breach of the Security Agreements and such
failure or breach shall not have been remedied within five days after the date
on which notice of such failure or breach shall have been given;

     (iv) Maker or Subsidiary shall commence, or there shall be commenced
against Maker or Subsidiary a case under any applicable bankruptcy or insolvency
laws as now or hereafter in effect or any successor thereto, or Maker or
Subsidiary commences any other proceeding under any reorganization, arrangement,
adjustment of debt, relief of debtors, dissolution, insolvency or liquidation or
similar law of any jurisdiction whether now or hereafter in effect relating to
Maker or Subsidiary, or there is commenced against Maker or Subsidiary any such
bankruptcy, insolvency or other proceeding which remains undismissed for a
period of 60 days; or Maker or Subsidiary is adjudicated insolvent or bankrupt;
or any order of relief or other order approving any such case or proceeding is
entered; or Maker or Subsidiary suffers any appointment of any custodian or the
like for it or any substantial part of its property which continues undischarged
or unstayed for a period of 60 days; or Maker or Subsidiary makes a general
assignment for the benefit of creditors; or Maker or Subsidiary shall fail to
pay, or shall state that it is unable to pay, or shall be unable to pay, its
debts generally as they become due; or Maker or Subsidiary shall call a meeting
of its creditors with a view to arranging a composition, adjustment or
restructuring of its debts; or Maker or Subsidiary shall by any act or failure
to act expressly indicate its consent to, approval of or acquiescence in any of
the foregoing; or any corporate or other action is taken by Maker or Subsidiary
for the purpose of effecting any of the foregoing;

     (v) Maker or Subsidiary shall default in any of its respective obligations
under any other note or any mortgage, credit agreement or other facility,
indenture agreement, factoring agreement or other instrument under which there
may be issued, or by which there may be secured or evidenced any indebtedness
for borrowed money or money due under any long term leasing or factoring
arrangement of Maker or Subsidiary, whether such indebtedness now exists or
shall hereafter be created and such default shall result in such indebtedness
becoming or being declared due and payable prior to the date on which it would
otherwise become due and payable;

     (vi) Maker's common stock (the "Common Stock") shall fail to be listed for
trading or shall be suspended from trading on the Over-the-Counter Market
without resuming trading and/or being relisted or having such suspension lifted,
in either case, for more than one trading day;

     (vii) Maker shall (a) be a party to any Change of Control Transaction (as
defined below), (b) agree to sell or dispose all or in excess of 50% of its
assets in one or more transactions (whether or not such sale would constitute a
Change of Control Transaction), (c) redeem or repurchase more than a de minimis
number of shares of Common Stock or other equity securities of Maker, or (d)
make any distribution or declare or pay any dividends (in cash or other
property, other than common stock) on, or purchase, acquire, redeem, or retire
any of Maker's capital stock, of any class, whether now or hereafter
outstanding. "Change of Control Transaction" means the occurrence of any of: (i)
an acquisition after the date hereof by an individual or legal entity or "group"
(as described in Rule 13d-5(b)(1) promulgated under



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the Exchange Act) of effective control (whether through legal or beneficial
ownership of capital stock of Maker, by contract or otherwise) of in excess of
50% of the voting securities of Maker, (ii) a replacement at one time or over
time of more than one-half of the members of Maker's board of directors which is
not approved by a majority of those individuals who are members of the board of
directors on the date hereof (or by those individuals who are serving as members
of the board of directors on any date whose nomination to the board of directors
was approved by a majority of the members of the board of directors who are
members on the date hereof), (iii) the merger of Maker with or into another
entity that is not wholly-owned by Maker, consolidation or sale of 50% or more
of the assets of Maker in one or a series of related transactions, or (iv) the
execution by Maker of an agreement to which Maker is a party or by which it is
bound, providing for any of the events set forth above in (i), (ii) or (iii); or

        (viii) any member of Maker's or Subsidiary's management shall cease to
be a member of Maker's or Subsidiary's senior management or shall cease to
perform any of the material functions and duties currently performed by such
person. For purposes hereof, "senior management" refers to the President, the
Chief Executive Officer, the Chief Financial Officer, the Chief Operations
Officer and any officer performing the customary function of such officers; or

        (ix) Maker shall unreasonably modify or change its method of accounting
or enter into, modify, or terminate any agreement currently existing, or at any
time hereafter entered into with any third party accounting firm or service
bureau for the preparation or storage of its accounting records, or restate or
modify its financial statements for any period of time prior to the date of this
Note; or

        (x) Maker shall cease to own 100% of the capital stock of Subsidiary.

     (b) If any Event of Default occurs, the full principal amount of this Note,
together with all accrued interest thereon, shall become, at the Payee's
election, immediately due and payable in cash. The Payee need not provide and
Maker hereby waives any presentment, demand, protest or other notice of any
kind, and the Payee may immediately and without expiration of any grace period
enforce any and all of its rights and remedies hereunder and all other remedies
available to it under applicable law. Such declaration may be rescinded and
annulled by Payee at any time prior to payment hereunder. No such rescission or
annulment shall affect any subsequent Event of Default or impair any right
consequent thereon.

4. Financings. Through and including the 360(th) day following the date of this
Note, Maker may not directly or indirectly, offer, sell or grant any option to
purchase (or announce any offer, sale, grant or any option to purchase) any of
its Common Stock or other securities which entitle the holder thereof to receive
Common Stock, including without limitation any debt, preferred stock or other
instrument or security that is, at any time during its life and under any
circumstances, convertible into or exchangeable for Common Stock. The
restrictions specified in this Section 4 shall not apply to (i) securities
issued as compensation or pursuant to stock options granted to employees,
officers and directors of the Maker pursuant to any stock option or other
similar plan duly adopted by the Maker, or (ii) securities issued pursuant to or
in a connection with a merger, acquisition or business combination by or with
the Maker or (iii) securities



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offered or sold in a single transaction (x) exempt from the registration
requirements of the Securities Act of 1933, as amended, and (y) resulting in net
proceeds to Maker of not less than $10,000,000 and at a price that is not
directly or indirectly, presently or at any later time, discounted to the market
price of the Common Stock at the time of such offering, and (z) not issued in
tandem with any options, warrants or other rights to acquire additional
securities of Maker or securities convertible into or exchangeable for
securities of Maker. In addition to being entitled to exercise all rights
provided herein or granted by law, including recovery of damages, Payee will be
entitled to specific performance of Maker's obligations under this Section 4.
Maker agrees that monetary damages may not be adequate compensation for any loss
incurred by reason of any breach of obligations described in this Section 4 and
hereby agrees to waive in any action for specific performance of any such
obligation the defense that a remedy at law would be adequate. The obligations
and agreements contained in this Section 4 shall survive through the period
expressed in this Section 4, regardless of any payment, prepayment or Event of
Default under this Note.

5. No Waiver of Payee's Rights. All payments of principal and interest shall be
made without setoff, deduction or counterclaim. No delay or failure on the part
of the Payee in exercising any of its options, powers or rights, nor any partial
or single exercise of its options, powers or rights shall constitute a waiver
thereof or of any other option, power or right, and no waiver on the part of the
Payee of any of its options, powers or rights shall constitute a waiver of any
other option, power or right. Maker hereby waives presentment of payment,
protest, and all notices or demands in connection with the delivery, acceptance,
performance, default or endorsement of this Note. Acceptance by the Payee of
less than the full amount due and payable hereunder shall in no way limit the
right of the Payee to require full payment of all sums due and payable hereunder
in accordance with the terms hereof.

6. Modifications. No term or provision contained herein may be modified, amended
or waived except by written agreement or consent signed by the party to be bound
thereby.

7. Cumulative Rights and Remedies; Usury. The rights and remedies of Payee
expressed herein are cumulative and not exclusive of any rights and remedies
otherwise available under this Note, the Security Agreements, or applicable law
(including at equity). The election of Payee to avail itself of any one or more
remedies shall not be a bar to any other available remedies, which Maker agrees
Payee may take from time to time. If it shall be found that any interest due
hereunder shall violate applicable laws governing usury, the applicable rate of
interest due hereunder shall be reduced to the maximum permitted rate of
interest under such law.

8. Use of Proceeds Maker shall use the proceeds from this Note hereunder for
working capital purposes and not for the satisfaction of any portion of Maker's
or Subsidiary's debt (other than payment of trade payables in the ordinary
course of Maker's business and prior practices), to redeem any of Maker's equity
or equity-equivalent securities or to settle any outstanding litigation.

9. Collection Expenses. If Payee shall commence an action or proceeding to
enforce this Secured Promissory Note, then Maker shall reimburse Payee for its
costs of collection and reasonable attorneys



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fees incurred with the investigation, preparation and prosecution of such action
or proceeding.

10. Severability. If any provision of this Note is declared by a court of
competent jurisdiction to be in any way invalid, illegal or unenforceable, the
balance of this Note shall remain in effect, and if any provision is
inapplicable to any person or circumstance, it shall nevertheless remain
applicable to all other persons and circumstances. If it shall be found that any
interest or other amount deemed interest due hereunder shall violate applicable
laws governing usury, the applicable rate of interest due hereunder shall
automatically be lowered to equal the maximum permitted rate of interest.

11. Successors and Assigns. This Note shall be binding upon Maker and its
successors and shall inure to the benefit of the Payee and its successors and
assigns. The term "Payee" as used herein, shall also include any endorsee,
assignee or other holder of this Note.

12. Lost or Stolen Promissory Note. If this Note is lost, stolen, mutilated or
otherwise destroyed, Maker shall execute and deliver to the Payee a new
promissory note containing the same terms, and in the same form, as this Note.
In such event, Maker may require the Payee to deliver to Maker an affidavit of
lost instrument and customary indemnity in respect thereof as a condition to the
delivery of any such new promissory note.

13. Due Authorization. This Note has been duly authorized, executed and
delivered by Maker and is the legal obligation of Maker, enforceable against
Maker in accordance with its terms.

14. Governing Law. All questions concerning the construction, validity,
enforcement and interpretation of this Note shall be governed by and construed
and enforced in accordance with the internal laws of the State of New York,
without regard to the principles of conflicts of law thereof. Each of Maker and
Payee agree that all legal proceedings concerning the interpretations,
enforcement and defense of this Note shall be commenced in the state and federal
courts sitting in the City of New York, Borough of Manhattan (the "New York
Courts"). Each of Maker and Payee hereby irrevocably submit to the exclusive
jurisdiction of the New York Courts for the adjudication of any dispute
hereunder (including with respect to the enforcement of this Note), and hereby
irrevocably waives, and agrees not to assert in any suit, action or proceeding,
any claim that it is not personally subject to the jurisdiction of any such
court, that such suit, action or proceeding is improper. Each of Maker and Payee
hereby irrevocably waive personal service of process and consents to process
being served in any such suit, action or proceeding by mailing a copy thereof
via registered or certified mail or overnight delivery (with evidence of
delivery) to the other at the address in effect for notices to it under this
Note and agrees that such service shall constitute good and sufficient service
of process and notice thereof. Nothing contained herein shall be deemed to limit
in any way any right to serve process in any manner permitted by law. Each of
Maker and Payee hereby irrevocably waive, to the fullest extent permitted by
applicable law, any and all right to trial by jury in any legal proceeding
arising out of or relating to this Note or the transactions contemplated hereby.

     The undersigned signs this Note as a marker and not as a surety or
guarantor or in any other capacity.

                                             e.DIGITAL CORPORATION

                                             By:
                                                --------------------------------
                                             Name:
                                             Title:



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