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                                                                     EXHIBIT 4.9


                                                                      NO. W-____

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT
AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
ANY STATE SECURITIES LAWS. SUCH SECURITIES MAY NOT BE SOLD OR TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SAID ACT AND ANY
APPLICABLE STATE SECURITIES LAWS.

                      WARRANT TO PURCHASE _________ SHARES
                               OF COMMON STOCK OF
                         AMERICAN TECHNOLOGY CORPORATION
                           (Void after March 31, 2003)

     This certifies that _________________________________ or its assigns (the
"Holder"), for value received, is entitled to purchase from AMERICAN TECHNOLOGY
CORPORATION, a Delaware corporation (the "Company"), having a place of business
at 13114 Evening Creek Drive South, San Diego, California 92128, a maximum of
______________ fully paid and nonassessable shares of the Company's Common Stock
("Common Stock") for cash at a price of $11.00 per share (the "Stock Purchase
Price") at any time or from time to time up to and including 5:00 p.m. (Pacific
time) on March 31, 2003 (the "Expiration Date"), upon surrender to the Company
at its principal office (or at such other location as the Company may advise the
Holder in writing) of this Warrant properly endorsed with the Form of
Subscription attached hereto duly filled in and signed and, if applicable, upon
payment in cash or by check of the aggregate Stock Purchase Price for the number
of shares for which this Warrant is being exercised determined in accordance
with the provisions hereof. The Stock Purchase Price and the number of shares
purchasable hereunder are subject to adjustment as provided in Section 3 of this
Warrant.

     This Warrant is subject to the following terms and conditions:

     1.  EXERCISE; ISSUANCE OF CERTIFICATES; PAYMENT FOR SHARES.

         1.1 GENERAL. This Warrant is exercisable at the option of the holder of
record hereof, at any time or from time to time, up to the Expiration Date for
all or any part of the shares of Common Stock (but not for a fraction of a
share) which may be purchased hereunder. The Company agrees that the shares of
Common Stock purchased under this Warrant shall be and are deemed to be issued
to the Holder hereof as the record owner of such shares as of the close of
business on the date on which this Warrant shall have been surrendered, properly
endorsed, the completed, executed Form of Subscription delivered and payment
made for such shares. Certificates for the shares of Common Stock so purchased,
together with any other securities or property to which the Holder hereof is
entitled upon such exercise, shall be delivered to the Holder hereof by the
Company at the Company's expense within five (5) business days after the rights
represented by this Warrant have been so exercised. In case of a purchase of
less than all the shares which may be purchased under this Warrant, the Company
shall cancel this Warrant

                                       1.
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and execute and deliver a new Warrant or Warrants of like tenor for the balance
of the shares purchasable under the Warrant surrendered upon such purchase to
the Holder hereof within five (5) business days. Each stock certificate so
delivered shall be in such denominations of Common Stock as may be requested by
the Holder hereof and shall be registered in the name of such Holder.
Notwithstanding anything to the contrary set forth above, each exercise of the
Warrant shall cover at least the lesser of (i) 10,000 shares of Common Stock or
(ii) the total number of shares of Common Stock subject to the Warrant.

         1.2 NET ISSUE EXERCISE.

             (a) This Section 1.2 shall not apply and shall have no force or
effect if, in accordance with the terms of the Series C Preferred Stock and
Warrant Purchase Agreement dated as of even date herewith between the Company
and the original holder of this Warrant (the "Purchase Agreement"), the shares
of Common Stock issuable upon exercise of this Warrant have been registered for
resale under the Securities Act of 1933, as amended, on a registration statement
on Form S-3, or another appropriate form.

             (b) Notwithstanding any provisions herein to the contrary, if the
fair market value of one share of the Company's Common Stock is greater than the
Stock Purchase Price (at the date of calculation as set forth below), in lieu of
exercising this Warrant for cash, the Holder may elect to receive shares equal
to the value (as determined below) of this Warrant (or the portion thereof being
canceled) by surrender of this Warrant at the principal office of the Company
together with the properly endorsed Form of Subscription and notice of such
election in which event the Company shall issue to the Holder a number of shares
of Common Stock computed using the following formula:

             X = Y (A-B)
                 -------
                    A

         Where X = the number of shares of Common Stock to be issued to the
Holder

                         Y = the number of shares of Common Stock purchasable
                         under the Warrant or, if only a portion of the Warrant
                         is being exercised, the portion of the Warrant being
                         canceled (at the date of such calculation)

                         A = the fair market value of one share of the Company's
                         Common Stock (at the date of such calculation)

                         B =  Stock Purchase Price (as adjusted to the date of
                         such calculation)

For purposes of the above calculation, fair market value of one share of Common
Stock shall be the average of the closing bid price of the Company's Common
Stock for the ten (10) trading days immediately preceding the date of exercise
as quoted on the principal exchange or market on which such securities are
traded.

                                       2.
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     2. SHARES TO BE FULLY PAID; RESERVATION OF SHARES. The Company covenants
and agrees that all shares of Common Stock which may be issued upon the exercise
of the rights represented by this Warrant will, upon issuance, be duly
authorized, validly issued, fully paid and nonassessable and free from all
preemptive rights of any stockholder and free of all taxes, liens and charges
with respect to the issue thereof. The Company further covenants and agrees
that, during the period within which the rights represented by this Warrant may
be exercised, the Company will at all times have authorized and reserved, for
the purpose of issue or transfer upon exercise of the subscription rights
evidenced by this Warrant, a sufficient number of shares of authorized but
unissued Common Stock, or other securities and property, when and as required to
provide for the exercise of the rights represented by this Warrant. The Company
will take all such action as may be necessary to assure that such shares of
Common Stock may be issued as provided herein without violation of any
applicable law or regulation, or of any requirements of any domestic securities
exchange upon which the Common Stock may be listed; provided, however, that the
Company shall not be required to effect a registration under Federal or State
securities laws with respect to such exercise other than as provided pursuant to
the Purchase Agreement. The Company will not take any action which would result
in any adjustment of the Stock Purchase Price (as set forth in Section 3 hereof)
if the total number of shares of Common Stock issuable after such action upon
exercise of all outstanding warrants, together with all shares of Common Stock
then outstanding and all shares of Common Stock then issuable upon exercise of
all options and upon the conversion of all convertible securities then
outstanding, would exceed the total number of shares of Common Stock then
authorized by the Company's Certificate of Incorporation.

     3. ADJUSTMENT OF STOCK PURCHASE PRICE AND NUMBER OF SHARES. The Stock
Purchase Price and the number of shares purchasable upon the exercise of this
Warrant shall be subject to adjustment from time to time upon the occurrence of
certain events described in this Section 3. Upon each adjustment of the Stock
Purchase Price, the Holder of this Warrant shall thereafter be entitled to
purchase, at the Stock Purchase Price resulting from such adjustment, the number
of shares obtained by multiplying the Stock Purchase Price in effect immediately
prior to such adjustment by the number of shares purchasable pursuant hereto
immediately prior to such adjustment, and dividing the product thereof by the
Stock Purchase Price resulting from such adjustment.

         3.1 SUBDIVISION OR COMBINATION OF STOCK. In case the Company shall at
any time subdivide its outstanding shares of Common Stock into a greater number
of shares, the Stock Purchase Price in effect immediately prior to such
subdivision shall be proportionately reduced, and conversely, in case the
outstanding shares of Common Stock of the Company shall be combined into a
smaller number of shares, the Stock Purchase Price in effect immediately prior
to such combination shall be proportionately increased.

         3.2 DIVIDENDS IN COMMON STOCK, OTHER STOCK, PROPERTY, RECLASSIFICATION.
If at any time or from time to time the Holders of Common Stock (or any shares
of stock or other securities at the time receivable upon the exercise of this
Warrant) shall have received or become entitled to receive, without payment
therefor,

                                       3.
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             (a) Common Stock or any shares of stock or other securities which
are at any time directly or indirectly convertible into or exchangeable for
Common Stock, or any rights or options to subscribe for, purchase or otherwise
acquire any of the foregoing by way of dividend or other distribution,

             (b) any cash paid or payable otherwise than as a cash dividend, or

             (c) Common Stock or additional stock or other securities or
property (including cash) by way of spinoff, split-up, reclassification,
combination of shares or similar corporate rearrangement, (other than shares of
Common Stock issued as a stock split or adjustments in respect of which shall be
covered by the terms of Section 3.1 above), then and in each such case, the
Holder hereof shall, upon the exercise of this Warrant, be entitled to receive,
in addition to the number of shares of Common Stock receivable thereupon, and
without payment of any additional consideration therefor, the amount of stock
and other securities and property (including cash in the cases referred to in
clause (b) above and this clause (c)) which such Holder would hold on the date
of such exercise had he been the holder of record of such Common Stock as of the
date on which holders of Common Stock received or became entitled to receive
such shares or all other additional stock and other securities and property.

         3.3 REORGANIZATION, RECLASSIFICATION, CONSOLIDATION, MERGER OR SALE.
If any recapitalization, reclassification or reorganization of the capital stock
of the Company, or any consolidation or merger of the Company with another
corporation, or the sale of all or substantially all of its assets or other
transaction shall be effected in such a way that holders of Common Stock shall
be entitled to receive stock, securities, or other assets or property (an
"Organic Change"), then, as a condition of such Organic Change, lawful and
adequate provisions shall be made by the Company whereby the Holder hereof shall
thereafter have the right to purchase and receive (in lieu of the shares of the
Common Stock of the Company immediately theretofore purchasable and receivable
upon the exercise of the rights represented hereby) such shares of stock,
securities or other assets or property as may be issued or payable with respect
to or in exchange for a number of outstanding shares of such Common Stock equal
to the number of shares of such stock immediately theretofore purchasable and
receivable upon the exercise of the rights represented hereby; provided,
however, that in the event the value of the stock, securities or other assets or
property (determined in good faith by the Board of Directors of the Company)
issuable or payable with respect to one share of the Common Stock of the Company
immediately theretofore purchasable and receivable upon the exercise of the
rights represented hereby is in excess of the Stock Purchase Price hereof
effective at the time of a merger and securities received in such
reorganization, if any, are publicly traded, then this Warrant shall expire
unless exercised prior to or simultaneous with such Organic Change. In the event
of any Organic Change, appropriate provision shall be made by the Company with
respect to the rights and interests of the Holder of this Warrant to the end
that the provisions hereof (including, without limitation, provisions for
adjustments of the Stock Purchase Price and of the number of shares purchasable
and receivable upon the exercise of this Warrant) shall thereafter be
applicable, in relation to any shares of stock, securities or assets thereafter
deliverable upon the exercise hereof. The Company will not effect any such
consolidation, merger or sale unless, prior to the consummation thereof, the
successor corporation (if other than the Company) resulting from

                                       4.
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such consolidation or the corporation purchasing such assets shall assume by
written instrument reasonably satisfactory in form and substance to the Holders
of a majority of the warrants to purchase Common Stock then outstanding,
executed and mailed or delivered to the registered Holder hereof at the last
address of such Holder appearing on the books of the Company, the obligation to
deliver to such Holder such shares of stock, securities or assets as, in
accordance with the foregoing provisions, such Holder may be entitled to
purchase.

         3.4 CERTAIN EVENTS. If any change in the outstanding Common Stock of
the Company or any other event occurs as to which the other provisions of this
Section 3 are not strictly applicable or if strictly applicable would not fairly
protect the purchase rights of the Holder of the Warrant in accordance with such
provisions, then the Board of Directors of the Company shall make an adjustment
in the number and class of shares available under the Warrant, the Stock
Purchase Price or the application of such provisions, so as to protect such
purchase rights as aforesaid. The adjustment shall be such as will give the
Holder of the Warrant upon exercise for the same aggregate Stock Purchase Price
the total number, class and kind of shares as he would have owned had the
Warrant been exercised prior to the event and had he continued to hold such
shares until after the event requiring adjustment.

         3.5 NOTICES OF CHANGE.

             (a) Within 10 business days after any adjustment in the number or
class of the shares subject to this Warrant and of the Stock Purchase Price, the
Company shall give written notice thereof to the Holder, setting forth in
reasonable detail and certifying the calculation of such adjustment.

             (b) The Company shall give written notice to the Holder at least 15
business days prior to the date on which the Company closes its books or takes a
record for determining rights to receive any dividends or distributions.

             (c) The Company shall also give written notice to the Holder at
least 15 business days prior to the date on which an Organic Change shall take
place.

     4. ISSUE TAX. The issuance of certificates for shares of Common Stock upon
the exercise of the Warrant shall be made without charge to the Holder of the
Warrant for any issue tax (other than any applicable income taxes) in respect
thereof; provided, however, that the Company shall not be required to pay any
tax which may be payable in respect of any transfer involved in the issuance and
delivery of any certificate in a name other than that of the then Holder of the
Warrant being exercised.

     5. CLOSING OF BOOKS. The Company will at no time close its transfer books
against the transfer of any warrant or of any shares of Common Stock issued or
issuable upon the exercise of any warrant in any manner which interferes with
the timely exercise of this Warrant.

     6. NO VOTING OR DIVIDEND RIGHTS; LIMITATION OF LIABILITY. Other than as set
forth herein, nothing contained in this Warrant shall be construed as conferring
upon the Holder hereof the right to vote or to consent or to receive notice as a
shareholder of the Company

                                       5.
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or any other matters or any rights whatsoever as a shareholder of the Company.
No dividends or interest shall be payable or accrued in respect of this Warrant
or the interest represented hereby or the shares purchasable hereunder until,
and only to the extent that, this Warrant shall have been exercised. No
provisions hereof, in the absence of affirmative action by any holder, and no
mere enumeration herein of the rights or privileges of the holder hereof, shall
give rise to any liability of such Holder for the Stock Purchase Price or as a
shareholder of the Company, whether such liability is asserted by the Company or
by its creditors.

     7. WARRANTS TRANSFERABLE. Subject to compliance with applicable federal and
state securities laws, this Warrant and all rights hereunder are transferable,
in whole or in part, without charge to the holder hereof (except for transfer
taxes), upon surrender of this Warrant properly endorsed. Each taker and holder
of this Warrant, by taking or holding the same, consents and agrees that this
Warrant, when endorsed in blank, shall be deemed negotiable, and that the holder
hereof, when this Warrant shall have been so endorsed, may be treated by the
Company, at the Company's option, and all other persons dealing with this
Warrant as the absolute owner hereof for any purpose and as the person entitled
to exercise the rights represented by this Warrant, or to the transfer hereof on
the books of the Company any notice to the contrary notwithstanding; but until
such transfer on such books, the Company may treat the registered owner hereof
as the owner for all purposes.

     8. RIGHTS AND OBLIGATIONS SURVIVE EXERCISE OF WARRANT. The rights and
obligations of the Company, of the holder of this Warrant and of the holder of
shares of Common Stock issued upon exercise of this Warrant, shall survive the
exercise of this Warrant.

     9.   MODIFICATION AND WAIVER.  This Warrant and any provision hereof may be
changed, waived, discharged or terminated only by an instrument in writing
signed by the party against which enforcement of the same is sought.

     10. NOTICES. Any notice, request or other document required or permitted to
be given or delivered to the holder hereof or the Company shall be delivered or
shall be sent by certified mail, postage prepaid, to each such holder at its
address as shown on the books of the Company or to the Company at the address
indicated therefor in the first paragraph of this Warrant or such other address
as either may from time to time provide to the other.

     11. BINDING EFFECT ON SUCCESSORS. This Warrant shall be binding upon any
corporation succeeding the Company by merger, consolidation or acquisition of
all or substantially all of the Company's assets. All of the obligations of the
Company relating to the Common Stock issuable upon the exercise of this Warrant
shall survive the exercise and termination of this Warrant. All of the covenants
and agreements of the Company shall inure to the benefit of the successors and
assigns of the holder hereof.

     12. DESCRIPTIVE HEADINGS AND GOVERNING LAW. The description headings of the
several sections and paragraphs of this Warrant are inserted for convenience
only and do not constitute a part of this Warrant. This Warrant shall be
construed and enforced in accordance with, and the rights of the parties shall
be governed by, the laws of the State of California.

                                       6.
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     13. LOST WARRANTS. The Company represents and warrants to the Holder hereof
that upon receipt of evidence reasonably satisfactory to the Company of the
loss, theft, destruction, or mutilation of this Warrant and, in the case of any
such loss, theft or destruction, upon receipt of an indemnity reasonably
satisfactory to the Company, or in the case of any such mutilation upon
surrender and cancellation of such Warrant, the Company, at its expense, will
make and deliver a new Warrant, of like tenor, in lieu of the lost, stolen,
destroyed or mutilated Warrant.

     14. FRACTIONAL SHARES. No fractional shares shall be issued upon exercise
of this Warrant. The Company shall, in lieu of issuing any fractional share, pay
the holder entitled to such fraction a sum in cash equal to such fraction
multiplied by the then effective Stock Purchase Price.

       15. SPECIFIC PERFORMANCE. The parties hereto hereby declare that it is
impossible to measure in money the damages which will accrue to a party hereto
or to their heirs, personal representatives, or assigns by reason of a failure
to perform any of the obligations under this Warrant and agree that the terms of
this Warrant shall be specifically enforceable. If any party hereto or his
heirs, personal representatives, or assigns institutes any action or proceeding
to specifically enforce the provisions hereof, any person against whom such
action or proceeding is brought hereby waives the claim or defense therein that
such party or such personal representative has an adequate remedy at law, and
such person shall not offer in any such action or proceeding the claim or
defense that such remedy at law exists.

     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
by its officers, thereunto duly authorized this ______ day of March, 2000.

                                        AMERICAN TECHNOLOGY CORPORATION,
                                        a Delaware corporation


                                        By:_____________________________
                                           Cornelius J. Brosnan
                                           President

ATTEST:


____________________________
Renee Warden
Secretary

                                       7.
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                                    EXHIBIT A

                                SUBSCRIPTION FORM

                                                 Date:  _________________, _____

American Technology Corporation
13114 Evening Creek Drive South
San Diego, California 92128

Attn:  President

Ladies and Gentlemen:

     The undersigned hereby elects to exercise the warrant issued to it by
     American Technology Corporation (the "Company") and dated March _____,
     2000, Warrant No. W-___ (the "Warrant") and to purchase thereunder
     __________________________________ shares of the Common Stock of the
     Company (the "Shares") at a purchase price of Six Dollars ($11.00) per
     Share or an aggregate purchase price of __________________________________
     Dollars ($__________) (the "Purchase Price").

Pursuant to the terms of the Warrant the undersigned has delivered the aggregate
Purchase Price herewith in full in cash or by certified check or wire transfer.

                                          Very truly yours,


                                          _______________________________
                                          By:
                                          Title:


                                       8.