<PAGE>   1
                                                                   EXHIBIT 4.9.6



================================================================================






                              AMFM OPERATING INC.,

                                   as Obligor

                                       and

                   THE GUARANTORS LISTED IN SCHEDULE I HERETO

                                       and


                   AMERICAN STOCK TRANSFER AND TRUST COMPANY,

                                   as Trustee

                   ------------------------------------------


                          SIXTH SUPPLEMENTAL INDENTURE

                            Dated as of June 2, 2000

                                       to

                                    Indenture

                          Dated as of December 19, 1996

                           Amended and Restated as of

                                October 28, 1997

                   ------------------------------------------


                                  $100,000,000

                   10 1/2% Senior Subordinated Notes due 2007


================================================================================




<PAGE>   2



                          SIXTH SUPPLEMENTAL INDENTURE

         SIXTH SUPPLEMENTAL INDENTURE dated as of June 2, 2000 among AMFM
OPERATING INC., a corporation duly organized and existing under the laws of the
State of Delaware (hereinafter called the "Company"), the guarantors listed in
Schedule I hereto (the "Guarantors"), and AMERICAN STOCK TRANSFER AND TRUST
COMPANY, a New York trust corporation, as trustee (the "Trustee");

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee the Amended and Restated Indenture dated as of December 19, 1996,
amended and restated as of October 28, 1997, among Katz Media Corporation, as
issuer, and the Trustee, as amended by the Second Supplemental Indenture dated
as of October 28, 1997 among Chancellor Media Corporation of Los Angeles
("CMCLA," as successor in interest to Katz Media Corporation), the guarantors
named therein and the Trustee, as further amended by the Third Supplemental
Indenture dated as of August 23, 1999 among CMCLA, the guarantors named therein
and the Trustee, as further amended by the Fourth Supplemental Indenture dated
as of November 19, 1999 among the Company (as successor in interest to CMCLA),
the guarantors named therein and the Trustee, and as further amended by the
Fifth Supplemental Indenture dated as of January 18, 2000 among the Company, the
guarantors named therein and the Trustee (collectively, the "Original
Indenture") to provide for the issuance of its 10 1/2% Senior Subordinated Notes
due 2007 (the "Notes"); and

         WHEREAS, Section 9.02 of the Original Indenture provides, among other
things, that, with the consent of the Holders of at least a majority in
aggregate principal amount of the Notes then outstanding, the Company, the
Guarantors and the Trustee may enter into indentures supplemental to the
Original Indenture for the purpose of amending any provision of the Original
Indenture or the Notes (other than as provided in Section 9.02 of the Original
Indenture); and

         WHEREAS, the Company desires to amend and delete certain provisions of
the Original Indenture; and

         WHEREAS, all action on the part of the Company necessary to authorize
its execution, delivery and performance of the Original Indenture, as further
supplemented by this Sixth Supplemental Indenture, has been duly taken; and

         WHEREAS, the Company has solicited the consent of the Holders of the
Notes to certain amendments to the Original Indenture (the "Amendments")
pursuant to that certain Consent Solicitation Statement dated April 27, 2000;
and

         WHEREAS, Holders of at least a majority in aggregate principal amount
of the Notes have consented to the Amendments and instruments evidencing such
consent have been delivered to the Trustee; and

         WHEREAS, the Company desires and has requested the Trustee and the
Guarantors to join in the execution and delivery of this Sixth Supplemental
Indenture for the purpose of amending the Original Indenture;


<PAGE>   3



         NOW THEREFORE, in consideration of the premises and for other good and
valuable consideration, it is mutually covenanted and agreed for the equal and
ratable benefit of all Holders of the Notes as follows, effective upon execution
hereof by the Company, the Trustee and the Guarantors:

                                   DEFINITION

         Section 1.1 Definition. When used herein, "Tender Offer Completion
Event" shall mean such time as each of the following events shall have occurred:
(i) the Company shall have completed a tender offer in accordance with the terms
and conditions set forth in the Company's Letter to Noteholders dated April 28,
2000, (ii) each holder of Notes that has tendered its Notes pursuant to the
tender offer shall have received payment for any Notes purchased pursuant to the
tender offer and (iii) the Company shall provide written notice of the events
described in (i) and (ii) to the Trustee.

                                   ARTICLE TWO
                        AMENDMENTS TO ORIGINAL INDENTURE

         Section 2.1 Deleted Definitions. Upon the occurrence of the Tender
Offer Completion Event,

         (a) Section 1.01 of the Original Indenture shall be amended by deleting
the following definitions in their entirety:

                  "Acquired Indebtedness"
                  "Acquired Preferred Stock"
                  "Asset Acquisition"
                  "Asset Sale"
                  "Asset Swap"
                  "Capital Lease Obligation"
                  "Capital Stock"
                  "Chancellor Broadcasting"
                  "Change of Control"
                  "Consolidated EBITDA"
                  "Consolidated Interest Expense"
                  "Consolidated Net Income"
                  "Consolidated Non-Cash Charges"
                  "Continuing Director"
                  "Contract Buy Out"
                  "DLJ"
                  "DLJMB"
                  "Eligible Institution"
                  "Existing Indebtedness"
                  "Financial Monitoring and Oversight Agreements"
                  "GAAP"
                  "Hedging Obligations"





                                       2
<PAGE>   4

                  "Hicks Muse"
                  "Initial Purchaser"
                  "Interim Credit Facility"
                  "Investments"
                  "Katz Notes"
                  "KCC Merger"
                  "KMG"
                  "KMSI"
                  "Leverage Ratio"
                  "Media Representation Venture"
                  "Moody's"
                  "NCC"
                  "Net Proceeds"
                  "Non-Cash Rent Expense"
                  "Non-Recourse Debt"
                  "Offering"
                  "Offering Memorandum"'
                  "Permitted Indebtedness"
                  "Permitted Investments"
                  "Permitted Liens"
                  "Productive Assets"
                  "pro forma"
                  "Qualified Capital Stock"
                  "Radio Broadcasting"
                  "Refinancing Indebtedness"
                  "Restricted Investment"
                  "Restricted Payment"
                  "SFAS No. 13"
                  "S&P"
                  "Significant Subsidiary"
                  "Tax Sharing Agreement"
                  "Tender Offer"
                  "Unrestricted Subsidiary"
                  "U.S. Government Obligations"
                  "U.S. Legal Tender"
                  "U.S. Person"
                  "Weighted Average Life to Maturity"
                  "Wholly Owned Subsidiary"

         (b) Section 1.02 of the Original Indenture shall be amended by deleting
the following definitions in their entirety:

                  "Affiliate Transaction"
                  "Asset Sale Payment"
                  "Change of Control Payment"

                                        3

<PAGE>   5



                  "Change of Control Offer"
                  "Incur"
                  "Net Proceeds Offer"
                  "Payment Date"
                  "Purchase Date"
                  "Restricted Payments"

         (c) The following definitions in Section 1.01 of the Original Indenture
shall be amended and restated in their entirety as follows:

                           "Company" means AMFM Operating Inc. until a successor
                  replaces it pursuant to this Indenture and thereafter means
                  such successor and also includes for the purposes of any
                  provision contained herein and required by the TIA any on the
                  Notes.

                           "Guarantor" means each of the Persons named as a
                  Guarantor in Schedule I to this Sixth Supplemental Indenture
                  and their respective successors and assigns.

         Section 2.2 Deleted Sections. Upon the occurrence of the Tender Offer
Completion Event, the following Sections of the Original Indenture shall be
deleted in their entirety: 3.08, 4.02, 4.03, 4.04, 4.05, 4.06, 4.07, 4.08, 4.09,
4.10, 4.11, 4.13, 4.14, 4.15, 4.16, 4.17, 4.18, 11.01, 11.02, 11.03, 11.04,
11.05, 11.06, 11.07 and 11.08.

         Section 2.3 Certain Modifications. Upon the occurrence to the Tender
Offer Completion Event, the text of each of the following Sections or
subsections of the Original Indenture shall be modified as follows:

         (a)      Section 2.06(i)(ii) shall be amended by deleting the clause
                  ",4.13, 4.14" in its entirety.

         (b)      Section 3.01 shall be amended to delete the second paragraph
                  thereof in its entirety.

         (c)      The first paragraph of Section 4.01 shall be amended and
                  restated in its entirety as follows:

                           "The Company shall pay the principal of, and premium,
                  if any, and accrued and unpaid interest on and Liquidated
                  Damages, if any, with respect to the Notes on the dates and in
                  the manner provided in the Notes. Holders of Notes must
                  surrender their Notes to the Paying Agent to collect principal
                  payments. Principal of, premium, if any, and accrued and
                  unpaid interest, and Liquidated Damages, if any, shall be
                  considered paid on the date due if the Paying Agent (other
                  than the Company or any of its Subsidiaries or any Affiliates
                  thereof), the Global Note Holder or each Holder that has
                  specified an account, holds, as of 12:00 noon New York City
                  time, money the Company deposited in immediately available
                  funds designated for and sufficient to pay in cash all
                  principal, premium, if any, and accrued and unpaid interest
                  on, and

                                        4

<PAGE>   6



                  Liquidated Damages, if any, then due; provided that, to the
                  extent that the Holders have not specified accounts, such
                  amounts shall be considered paid on the date due if the
                  Company mails a check for such amounts on such date. The
                  Paying Agent shall return to the Company, no later than five
                  days following the date of payment, any money (including
                  accrued interest) that exceeds the amount of principal,
                  premium, if any, accrued and unpaid interest, and Liquidated
                  Damages, if any, paid on the Notes. The Company shall pay all
                  Liquidated Damages, if any, in the same manner on the dates
                  and in the amounts set forth in the Registration Rights
                  Agreement. If any Liquidated Damages become payable, the
                  Company shall not later than 3 Business Days prior to the date
                  that any payment of Liquidated Damages is due (i) deliver an
                  Officers' Certificate to the Trustee setting forth the amount
                  of Liquidated Damages payable to Holders and (ii) instruct the
                  Paying Agent to pay such amount of Liquidated Damages to
                  Holders entitled to receive such Liquidated Damages."

         (d)      Section 5.01 shall be amended and restated in its entirety to
                  read as follows:

                  "SECTION 5.01.    MERGER, CONSOLIDATION OR SALE OF ASSETS.

                           The Company shall not consolidate or merge with or
                  into (whether or not the Company is the surviving entity), or
                  sell, assign, transfer, lease, convey or otherwise dispose of
                  all or substantially all of its properties or assets in one or
                  more related transactions to another corporation, Person or
                  entity unless (i) the Company is the surviving corporation or
                  the entity or Person formed by or surviving any such
                  consolidation or merger (if other than the Company) or to
                  which such sale, assignment, transfer, lease, conveyance or
                  other disposition shall have been made is a corporation
                  organized or existing under the laws of the United States, any
                  state thereof or the District of Columbia; and (ii) the entity
                  or Person formed by or surviving any such consolidation or
                  merger (if other than the Company) or the entity or Person to
                  which such sale, assignment, transfer, lease, conveyance or
                  other disposition will have been made assumes all the
                  obligations of the Company under the Notes and this Indenture
                  pursuant to a supplemental indenture in form reasonably
                  satisfactory to the Trustee."

         (e)      Section 6.01 shall be amended and restated in its entirety to
                  read as follows:

                  "SECTION 6.01.    EVENTS OF DEFAULT.

                  (a)      An Event of Default is:

                           (i)      default for 30 days in the payment when due
                                    of interest on, or Liquidated Damages, if
                                    any, with respect to the Notes whether or
                                    not prohibited by Article 10 hereof;

                           (ii)     default in payment when due of principal or
                                    premium, if any, on the

                                        5

<PAGE>   7



                                    Notes at maturity, upon redemption or
                                    otherwise whether or not prohibited by
                                    Article 10 hereof;

                           (iii)    [intentionally left blank];

                           (iv)     [intentionally left blank];

                           (v)      [intentionally left blank];

                           (vi)     [intentionally left blank];

                           (vii)    [intentionally left blank];

                           (viii)   in existence when the Company:

                                    (A)      commences a voluntary case,

                                    (B)      consents to the entry of an order
                                             for relief against it in an
                                             involuntary case,

                                    (C)      consents to the appointment of a
                                             Custodian of it or for all or
                                             substantially all of its property,
                                             or

                                    (D)      makes a general assignment for the
                                             benefit of its creditors, and

                           (ix)     in existence when a court of competent
                                    jurisdiction enters an order or decree under
                                    any Bankruptcy Law that:

                                    (A)      is for relief against the Company,

                                    (B)      appoints a Custodian of the
                                             Company, or

                                    (C)      orders the liquidation of the
                                             Company,

                           and any such order or decree remains unstayed and in
                           effect for 60 days.

                           The term "Custodian" means any receiver, trustee,
                  assignee, liquidator or similar official under any Bankruptcy
                  Law."

         (f)      Section 6.02 shall be amended and restated in its entirety to
                  read as follows:

                  "SECTION 6.02.    ACCELERATION.

                           If any Event of Default occurs and is continuing
                           (other than an Event of

                                        6

<PAGE>   8



                  Default under Section 6.01(a)(viii) or (ix) hereof), the
                  Trustee or the Holders of at least 25% in principal amount of
                  the then outstanding Notes may declare all the Notes to be due
                  and payable by notice in writing to the Company and the
                  Trustee specifying the respective Event of Default and that it
                  is a "notice of acceleration" (the "Acceleration Notice"), and
                  the same (i) shall become immediately due and payable or (ii)
                  if there are any amounts outstanding under the Credit
                  Agreement, shall become immediately due and payable upon the
                  first to occur of an acceleration under the Credit Agreement
                  or five Business Days after receipt by the Company and the
                  Representative under the Credit Agreement of such Acceleration
                  Notice but only if such Event of Default is then continuing.
                  Notwithstanding the foregoing, in the case of an Event of
                  Default arising from Section 6.01(a)(viii) or (ix) hereof, all
                  outstanding Notes will become due and payable without further
                  action or notice."

         (g)      Section 8.01 shall be amended and restated in its entirety to
                  read as follows:

                  "SECTION 8.01.    OPTION TO EFFECT LEGAL DEFEASANCE OR
                                    COVENANT DEFEASANCE.

                           The Company may, at the option of its Board of
                  Directors evidenced by a resolution set forth in an Officers'
                  Certificate, at any time, elect to have either Section 8.02 or
                  8.03 hereof be applied to all outstanding Notes upon
                  compliance with the conditions set forth below in this Article
                  8."

         (h)      Section 8.02 shall be amended and restated in its entirety to
                  read as follows:

                  "SECTION 8.02.    LEGAL DEFEASANCE AND DISCHARGE.

                           Upon the Company's exercise under Section 8.01 hereof
                  of the option applicable to this Section 8.02, the Company
                  shall, subject to the satisfaction of the conditions set forth
                  in Section 8.04 hereof, be deemed to have been discharged from
                  its obligations with respect to all outstanding Notes on the
                  date the conditions set forth below are satisfied
                  (hereinafter, "Legal Defeasance"). For this purpose, Legal
                  Defeasance means that the Company shall be deemed to have paid
                  and discharged the entire Indebtedness represented by the
                  outstanding Notes, which shall thereafter be deemed to be
                  "outstanding" only for the purposes of Section 8.05 hereof and
                  the other Sections of this Indenture referred to in (a) and
                  (b) below, and to have satisfied all its other obligations
                  under such Notes and this Indenture (and the Trustee, on
                  demand of and at the expense of the Company, shall execute
                  proper instruments acknowledging the same), except for the
                  following provisions which shall survive until otherwise
                  terminated or discharged hereunder: (a) the rights of Holders
                  of outstanding Notes to receive payments in respect of the
                  principal of, premium, if any, and interest and Liquidated
                  Damages, if any, on such Notes when such payments are due or
                  on the redemption date, as the case may be, from the trust
                  referred to in Section 8.04(a); (b) the Company's obligations
                  with respect to such Notes under Sections 2.02, 2.03, 2.04,
                  2.05, 2.06, 2.07, 2.10 and 4.12 hereof; (c) the rights,
                  powers, trusts, duties and immunities of the Trustee including
                  without limitation thereunder Section 7.07, 8.05 and 8.07
                  hereunder and the Company's obligations in connection
                  therewith; (d) the Company's rights to redeem Notes under
                  Section 3.07 hereof; and (e) the provisions of this Article 8.
                  Subject to compliance with this Article 8, the Company may
                  exercise its option under this Section 8.02 notwithstanding
                  the prior exercise of its option under Section 8.03 hereof."

                                        7

<PAGE>   9




         (i) Section 8.03 shall be amended and restated in its entirety to read
as follows:

                  "SECTION 8.03.    COVENANT DEFEASANCE

                           Upon the Company's exercise under Section 8.01 hereof
                  of the option applicable to this Section 8.03, the Company
                  shall, subject to the satisfaction of the conditions set forth
                  in Section 8.04 hereof, be released from its obligations under
                  the covenants contained in Section 5.01 hereof with respect to
                  the outstanding Notes on and after the date the conditions set
                  forth below are satisfied (hereinafter, "Covenant
                  Defeasance"), and the Notes shall thereafter be deemed not
                  "outstanding" for the purposes of any direction, waiver,
                  consent or declaration or act of Holders (and the consequences
                  of any thereof) in connection with such covenants, but shall
                  continue to be deemed "outstanding" for all other purposes
                  hereunder (it being understood that such Notes shall not be
                  deemed outstanding for accounting purposes). For this purpose,
                  Covenant Defeasance means that, with respect to the
                  outstanding Notes, the Company or its Subsidiaries may omit to
                  comply with and shall have no liability in respect of any
                  term, condition or limitation set forth in any such covenant,
                  whether directly or indirectly, by reason of any reference
                  elsewhere herein to any such covenant or by reason of any
                  reference in any such covenant to any other provision herein
                  or in any other document and such omission to comply shall not
                  constitute a Default or an Event of Default under Section 6.01
                  hereof, but, except as specified above, the remainder of this
                  Indenture and such Notes shall be unaffected thereby. In
                  addition, upon the Company's exercise under Section 8.01
                  hereof of the option applicable to this Section 8.03 hereof,
                  subject to the satisfaction of the conditions set forth in
                  Section 8.04 hereof, Sections 6.01(a)(i) through 6.01(a)(vii)
                  hereof shall not constitute Events of Default."

         (j) The first sentence of Section 8.04 shall be amended and restated in
its entirety to read as follows:

                           "The following shall be the conditions to the
                  application of either Section 8.02 or 8.03 hereof to the
                  outstanding Notes:"

         (k) The first paragraph of Section 9.01 shall be amended and restated
in its entirety to read as follows:

                           "Notwithstanding Section 9.02 hereof, the Company and
                  the Trustee may amend or supplement this Indenture or the
                  Notes without the consent of any Holder: (a) to cure any
                  ambiguity, defect or inconsistency; (b) to provide for
                  uncertificated Notes in addition to or in place of
                  certificated Notes; (c) to provide for the assumption by a
                  successor corporation of the Company's Obligations to the
                  Holders in the event of a disposition pursuant to Article 5;
                  (d) to comply with SEC's requirements to effect or maintain
                  the qualification of this Indenture under the TIA; (e) to make
                  any change that does not materially adversely affect any
                  Holder's legal rights under this Indenture; (f) to evidence
                  and provide for a successor Trustee; (g) to add additional
                  covenants or Events of Default; or (h) to secure the Notes."

                                        8

<PAGE>   10



         (l) Section 9.02 shall be amended and restated in its entirety to read
as follows:

                  "SECTION 9.02.    AMENDMENTS AND SUPPLEMENTS REQUIRING CONSENT
                                    OF HOLDERS.

                           Subject to Section 6.07 hereof and Section 10.13, the
                  Company and the Trustee may amend or supplement this Indenture
                  or the Notes with the consent of the holders of at least a
                  majority in principal amount of the Notes then outstanding
                  (including, without limitation, consents obtained in
                  connection with a purchase of, or tender offer or exchange
                  offer for Notes), and any existing Default or Event of Default
                  (other than a payment Default) or compliance with any
                  provision of the Indenture or the Notes may be waived with the
                  consent of the holders of a majority in principal amount of
                  the then outstanding Notes (including consents obtained in
                  connection with a tender offer or exchange offer for Notes).

                           Upon the Company's request and after receipt by the
                  Trustee of a resolution of the Board of Directors authorizing
                  the execution of any supplemental indenture, evidence of the
                  Holders' consent, and the documents described in Section 9.06
                  hereof, the Trustee shall join with the Company in the
                  execution of such amended or supplemental indenture unless
                  such amended or supplemental indenture affects the Trustee's
                  own rights, duties or immunities under this Indenture or
                  otherwise, in which case the Trustee may in its discretion,
                  but not be obligated to, enter into such amended or
                  supplemental indenture.

                           It shall not be necessary for the consent of the
                  Holders under this Section 9.02 to approve the particular form
                  of any proposed amendment or waiver, but it shall be
                  sufficient if such consent approves the substance thereof.
                  However, without the consent of each Holder affected, an
                  amendment, supplement or waiver may not (with respect to any
                  Notes held by a non-consenting Holder): (i) reduce the
                  principal amount of Notes whose holders must consent to an
                  amendment, supplement or waiver, (ii) reduce the principal of
                  or change the fixed maturity of any Note or alter the
                  provisions with respect to the redemption of the Notes in a
                  manner adverse to Holders, (iii) reduce the rate of or change
                  the time for payment of interest on any Note, (iv) waive a
                  Default or Event of Default in the payment of principal of or
                  premium, if any, or interest on the Notes (except a rescission
                  of acceleration of the Notes by the holders of at least a
                  majority in aggregate principal amount of the Notes and a
                  waiver of the payment default that resulted from such
                  acceleration), (v) make any Note payable in money other than
                  that stated in the Notes, (vi) make any change in the
                  provisions of the Indenture relating to waivers of past
                  Defaults or the rights of holders of Notes to receive payments
                  of principal of or premium, if any, or interest on the Notes,
                  (vii) waive a redemption payment with respect to any Note or
                  (viii) make any change in the foregoing amendment and waiver
                  provisions. In addition, any amendment to the provisions of
                  Article 10 hereof will require the consent of the holders of
                  at least 75% in aggregate principal amount of the Notes then
                  outstanding if such

                                        9

<PAGE>   11



                  amendment would adversely affect the rights of holders of
                  Notes."

         (m) Section 10.01 shall be amended and restated in its entirety to read
as follows:

                  "SECTION 10.01. AGREEMENT TO SUBORDINATE.

                           The Company agrees, and each Holder by accepting a
                  Note agrees, that the payment of principal of, premium,
                  interest and Liquidated Damages, if any, on the Notes shall be
                  subordinated in right of payment, to the extent and in the
                  manner provided in this Article 10, to the prior payment in
                  full in cash or Marketable Securities of all Senior Debt,
                  whether outstanding on the date hereof or thereafter
                  incurred."

         (n) The second paragraph of Section 10.09 shall be amended and restated
in its entirety to read as follows:

                           "Without in any way limiting the generality of the
                  foregoing paragraph, the holders of the Senior Debt may, at
                  any time and from time to time, without the consent of or
                  notice to the Trustee or the Holders, without incurring
                  responsibility to the Holders and without impairing or
                  releasing the subordination provided in this Article or the
                  obligations hereunder of the Holders to the holders of Senior
                  Debt, do any one or more of the following: (a) change the
                  manner, place or terms of payment or extend the time or
                  payment of, or renew or alter, Senior Debt or any instrument
                  evidencing the same or any agreement under which Senior Debt
                  is outstanding; provided, however, that any such alteration
                  shall not increase the amount of Senior Debt outstanding in a
                  manner prohibited by this Indenture; (b) sell, exchange,
                  release or otherwise deal with any property pledged, mortgaged
                  or otherwise securing Senior Debt; (c) release any Person
                  liable in any manner for the collection of Senior Debt; and
                  (d) exercise or refrain from exercising any rights against the
                  Company or any other Person; provided, however, that in no
                  event shall any such actions limit the right of the Holder to
                  take any action to accelerate the maturity of the Notes in
                  accordance with the provisions set forth in Article 6 or to
                  pursue any rights or remedies against the parties to the
                  Indenture under the Indenture or under applicable laws if the
                  taking of such action does not otherwise violate the terms of
                  this Article."

         (o) Section 12.08 shall be amended and restated in its entirety to read
as follows:

                  "SECTION 12.08. NO RECOURSE AGAINST OTHERS.

                           No officer, employee, director, incorporator or
                  stockholder of the Company shall have any liability for any
                  Obligations of the Company under the Notes or this Indenture,
                  or for any claim based on, in respect of, or by reason of,
                  such Obligations or the creation of any such Obligation. Each
                  Holder by accepting a Note waives and releases all such
                  liability, and such waiver and

                                       10

<PAGE>   12



                  release is part of the consideration for the issuance of the
                  Notes."

         Section 2.4 Guarantees. The Guarantors are hereby released from any and
all obligations they have or may have with respect to any Guarantee contemplated
by the Indenture as the Indenture existed before giving effect to the amendments
herein.

                                  ARTICLE THREE

                            MISCELLANEOUS PROVISIONS

         Section 3.1 Execution as Supplemental Indenture. This Sixth
Supplemental Indenture is executed and shall be construed as an indenture
supplemental to the Original Indenture and, as provided in the Original
Indenture, this Sixth Supplemental Indenture forms a part thereof. Except as
herein expressly otherwise defined, the use of the terms and expressions herein
is in accordance with the definitions, uses and constructions contained in the
Original Indenture.

         Section 3.2 Responsibility for Recitals, etc. The recitals herein shall
be taken as the statements of the Company, and the Trustee assumes no
responsibility for the correctness thereof. The Trustee makes no representations
as to the validity or sufficiency of this Sixth Supplemental Indenture.

         Section 3.3 Provisions Binding on Company's Successors. All of the
covenants, stipulations, promises and agreements made in this Sixth Supplemental
Indenture by the Company, the Guarantors and the Trustee shall bind their
respective successors and assigns whether so expressed or not.

         Section 3.4 Governing Law. This Sixth Supplemental Indenture shall be
deemed to be a contract made under the laws of the State of New York and, for
all purposes, shall be construed in accordance with the laws of said State.

         Section 3.5 Execution and Counterparts. This Sixth Supplemental
Indenture may be executed in any number of counterparts, each of which shall be
an original, but such counterparts shall together constitute but one and the
same instrument.

         Section 3.6 Trustee Disclaimer. The Trustee accepts the amendment of
the Indenture effected by this Sixth Supplemental Indenture and agrees to
execute the trust created by the Indenture as hereby amended, but on the terms
and conditions set forth in the Indenture, including the terms and provisions
defining and limiting the liabilities and responsibilities of the Trustee, which
terms and provisions shall in like manner define and limit its liabilities and
responsibilities in the performance of the trust created by the Indenture as
hereby amended, and without limiting the generality of the foregoing, the
Trustee shall not be responsible in any manner whatsoever for or with respect to
any of the recitals or statements contained herein, all of which recitals or
statements are made solely by the Company and the Guarantors, or for or with
respect to (i) the validity or sufficiency of this Sixth Supplemental Indenture
or any of the terms

                                       11

<PAGE>   13



or provisions hereof, (ii) the proper authorization hereof by the Company and
the Guarantors by corporate action or otherwise, (iii) the due execution hereof
by the Company and the Guarantors or (iv) the consequences (direct or indirect
and whether deliberate or inadvertent) of any amendment herein provided for, and
the Trustee makes no representation with respect to any such matters.

         Section 3.7 Trust Indenture Act to Control. If and to the extent that
any provision of this Sixth Supplemental Indenture limits, qualifies, or
conflicts with another provision included in the Original Indenture or in this
Sixth Supplemental Indenture which is required to be included in or is or is
deemed to be applicable to this Sixth Supplemental Indenture by any of Sections
310 to 317, inclusive, of the Trust Indenture Act of 1939, such required or
other applicable provision shall control.

                  [Remainder of page intentionally left blank]

                                       12

<PAGE>   14



         IN WITNESS WHEREOF, the parties hereto have caused this Sixth
Supplemental Indenture to be duly executed, and their respective corporate seals
to be hereunto affixed and attested, all as of the date first written above.

                              AMFM OPERATING INC.
                              as Obligor



                              By:      /s/ W. Schuyler Hansen
                                  ---------------------------
                                       W. Schuyler Hansen
                                       Senior Vice President and
                                       Chief Accounting Officer


Attest:    /s/
        ----------------------


                              ON BEHALF OF EACH OF THE GUARANTORS LISTED ON
                              SCHEDULE I HERETO



                              By:       /s/ Kathy Archer
                                  ---------------------------
                                       Kathy Archer
                                       Senior Vice President


Attest:   /s/
        ----------------------


                              AMERICAN STOCK TRANSFER & TRUST
                              COMPANY, as Trustee



                              By:       /s/
                                  ---------------------------
                                       Name:
                                       Title:


Attest:    /s/
        ----------------------




                                       13

<PAGE>   15



                                   SCHEDULE I

         AMFM OPERATING INC. 10 1/2% SENIOR SUBORDINATED NOTES DUE 2007



<TABLE>
<CAPTION>
                                                                                STATE OF
                           GUARANTORS                                         ORGANIZATION
                           ----------                                         ------------
<S>                                                                           <C>
Amcast Radio Sales, Inc.                                                        Delaware
AMFM Air Services, inc.                                                         Delaware
AMFM Broadcasting, Inc.                                                         Delaware
AMFM Houston, Inc.                                                              Delaware
AMFM LA, LLC                                                                    Delaware
AMFM Massachusetts, Inc.                                                        Delaware
AMFM Michigan, Inc.                                                             Delaware
AMFM New York, Inc.                                                             Delaware
AMFM Ohio, Inc.                                                                 Delaware
AMFM Pennsylvania, Inc.                                                         Delaware
AMFM Radio Group, Inc.                                                          Delaware
AMFM Radio Licenses, LLC                                                        Delaware
AMFM/Riverside Broadcasting, Inc.                                               Delaware
AMFM San Diego, Inc.                                                            Delaware
AMFM Shamrock Texas, Inc.                                                         Texas
AMFM Systems, Inc.                                                              Delaware
AMFM Texas, LLC                                                                 Delaware
AMFM Texas Broadcasting, LP                                                     Delaware
AMFM Texas Licenses, LP                                                         Delaware
AMFM Washington DC, Inc.                                                        Delaware
AMFM/WAXQ, Inc.                                                                 Delaware
Broadcast Architecture, Inc.                                                  Massachusetts
Capstar Acquisition Company, Inc.                                               Delaware
Capstar Radio Operating Company                                                 Delaware
Capstar TX Limited Partnership                                                  Delaware
Chancellor Marketing Group, Inc.                                                Virginia
Christal Radio Sales, Inc.                                                      Delaware
Cleveland Radio Licenses, LLC                                                   Delaware
Eastman Radio Sales, Inc.                                                       Delaware
Jamboree in the Hills, Inc.                                                     Delaware
Katz Cable Corporation                                                          Delaware
Katz Communications, Inc.                                                       Delaware
Katz Media Corporation                                                          Delaware
Katz Millennium Marketing, Inc.                                                 Delaware
Katz Millennium Sales & Marketing, Inc.                                         Delaware
Osborn Entertainment Enterprises Corporation                                    Delaware
Radio 100, LLC                                                                  Delaware
</TABLE>


                                       14

<PAGE>   16



<TABLE>
<CAPTION>
                                                                                STATE OF
                           GUARANTORS                                         ORGANIZATION
                           ----------                                         ------------
<S>                                                                           <C>
The AMFM Radio Networks, Inc.                                                   Delaware
The National Payroll Company, Inc.                                              Delaware
WAXQ License Corp.                                                              Delaware
WLTW License Corp.                                                              Delaware
WPYX, Inc.                                                                      New York
Zebra Broadcasting Corporation                                                    Ohio
</TABLE>


                                       15