<PAGE>
                       AMENDMENT NO. 6 TO LOAN AGREEMENT

     THIS AMENDMENT NO. 6 TO LOAN AGREEMENT (the ''Amendment'') is made and
entered into as of October 10, 2001, by and between LaSALLE BANK NATIONAL
ASSOCIATION, f/k/a/ LaSALLE NATIONAL BANK, a national banking association (the
''Lender''), and KOSS CORPORATION, a Delaware corporation (the ''Borrower'').

                                R E C I T A L S:
                                ---------------

     Borrower and Lender entered into that certain Loan Agreement dated February
17, 1995, as amended by that certain Amendment No. 1 to Loan Agreement dated
June 15, 1995, at further amended by that certain Amendment No. 2 to Loan
Agreement dated May 20, 1996, as further amended by that certain Amendment No. 3
to Loan Agreement dated December 31, 1997, as further amended by that certain
Amendment No. 4 to Loan Agreement dated April 29, 1999, and as further amended
by that certain Amendment No. 5 dated December 15, 1999 (collectively, the
''Loan Agreement''), pursuant to which Lender agreed to provide Borrower with a
revolving line of credit up to $10,000,000.00 (the ''Revolving Loan''); and

     Borrower has requested Lender to extend the Maturity Date of the Revolving
Loan to November 1, 2002, and Lender has agreed to do so provided, among other
things, Borrower executes and delivers this Amendment.

     NOW THEREFORE, in consideration of the premises which are incorporated
herein by this reference, and other good and valuable consideration, the receipt
and sufficiency of which is hereby acknowledged, the parties agree as follows:

     1.  Section 2.1(A) of the Loan Agreement shall be deleted in its entirety
and replaced with the following new Section 2.1(A):

     Subject to the terms and conditions of this Agreement, on the date upon
     which all terms and conditions of the Documents have been met or fulfilled
     to the satisfaction of Lender (the ''Closing Date''), the Lender agrees to
     make loans to Borrower on a revolving basis (such loans being herein called
     individually, a ''Revolving Loan'', and collectively, the ''Revolving
     Loans'') from time to time in such amounts as Borrower may from time to
     time request up to an aggregate amount outstanding of $10,000,000.00;
     provided, however, that (i) each borrowing by Borrower hereunder with
     respect to any Revolving Loan shall be in the aggregate principal amount of
     at least $10,000.00; (ii) the Lenders's commitment to make Revolving Loans
     shall remain in effect for a period to and including November 1, 2002 (the
     ''Revolver Termination Date''); (iii)

                                       1
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     notwithstanding any provision herein to the contrary (1) upon the
     occurrence and continuance of any Event of Default, and in each such
     event, the Lender may, in its sole discretion, immediately cease to make
     Revolving Loans; and (2) on the Revolver Termination Date, Borrower shall
     repay to the Lender all Revolving Loans, plus interest accrued to the date
     of payment; and (iv) for a period of at least 30 consecutive days during
     each fiscal year of Borrower, the amount of Revolving Loans outstanding
     shall not exceed $2,000,000.00.

     2.   Subsection 2.1(B)(b) of the Loan Agreement shall be deleted in its
entirety and replaced with the following new Subsection 2.1(B)(b):

     (b)  all Letters of Credit shall expire prior to November 1, 2002.

     3.   Subsection 5.1(S) of the Loan Agreement shall be deleted in its
entirety and replaced with the following new Subsection 5.1(S):

          (s)  Tangible Net Worth. Borrower, on a consolidated basis, shall not
cause, suffer or permit its Tangible Net Worth (including adjustment for
transactions with Affiliates) to be less than $10,000,000.00 at any time.

     4.   Borrower shall deliver to Lender as a condition to Lender's
undertakings as provided hereunder, note amendments, a copy of its Articles of
Incorporation certified by the Delaware Secretary of State, a directors'
consent, secretary's certificate and such other documents as Lender shall
request, each in form and substance satisfactory to Lender and its counsel.

     5.   All references to "the Agreement" in the Loan Agreement shall mean
the Loan Agreement as amended by this Amendment. All references to "the Loan,"
"the Loans," in the Loan Agreement shall include the loan amendments made
hereunder. All references to "the Documents" in the Loan Agreement shall
include this Amendment, the amendment to the Revolving Note and any other
instrument or document required hereunder, whether now existing or at any time
hereafter arising. All references to "the Revolving Note" and in Loan Agreement
shall include the amendments thereto.

     6.   All of the agreements, representations, covenants and obligations set
forth in the Loan Agreement and hereby reaffirmed and restated as of the date
of this Amendment. All representations and warranties contained in the Loan
Agreement remain true and correct as of the date of this Amendment.

     7.    Borrower agrees to pay all fees and out-of-pocket expenses of Lender
including, without limitation, outside counsel to the Lender in connection with
the preparation of this Amendment, and any and all
<PAGE>
agreements, instruments and documents required or contemplated by this
Amendment.

          8.   Except as specifically amended and modified by this Amendment:
(a) the Loan Agreement shall remain in full force and effect and is hereby
restated and incorporated herein by this reference; and (b) all terms defined in
the Loan Agreement shall have the same meanings herein as therein.

          IN WITNESS WHEREOF, the parties hereto have caused this Amendment No.
6 to be duly executed and delivered at Chicago, Illinois, as of the date first
above written.

LaSALLE BANK NATIONAL ASSOCIATION KOSS CORPORATION


By: /s/  James J. Hess         By: /s/ Michael J. Koss
   --------------------           --------------------
Title: Vice President          Title: CEO President
      -----------------              -----------------


                               ATTEST:


                               By: /s/  Laura J. Acuff
                                  --------------------
                               Title: Notary Public
                                     -----------------



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<PAGE>
                       UNANIMOUS CONSENT OF DIRECTORS OF
                                KOSS CORPORATION

     The undersigned, constituting all the directors of Koss Corporation, a
Delaware corporation (the "Corporation"), do hereby consent and agree to the
adoption of the following resolutions:

     WHEREAS, the Corporation is and may, from time to time, be indebted to
LaSalle Bank National Association f/k/a LaSalle National Bank ("Lender") by
virtue of loans, advances and other financial accommodations made or to be made
to Corporation by Lender.

NOW, THEREFORE, BE IT RESOLVED, that the president and security of this
Corporation be and each of them, acting alone, is hereby authorized to execute
and deliver, in the name and on behalf of this Corporation, that certain
Amendment No. 6 to Loan Agreement (the "Amendment"), and Amendment No. 5 to
Revolving Note by and between Lender and the Corporation, and any other
documents required or contemplated under any of such document (collectively,
the "Documents"), with such changes therein as such officer in executing the
same shall approve; the execution thereof by such officer to be conclusive
evidence of the approval thereof by such officer and by the directors of this
Corporation.

     FURTHER RESOLVED, that the president of this Corporation, acting alone, is
hereby authorized to make such actions and execute and deliver such
certificates, financing statements, instruments, assignments, notices
and documents as may be required of as such officer may deem necessary,
advisable or proper in order to carry out and perform the obligations of the
Corporation under the Documents all such actions to be performed in such
manner, and all such certificates, financing statements, instruments, notices
and documents to be executed and delivered in such form, as the officer
performing or executing the same shall approve, the performance or execution
thereof by such officer to be conclusive evidence of the approval thereof by
such officer and this board.

     FURTHER RESOLVED, that the president, vice president-finance and secretary
of this Corporation and each of them, acting alone, is hereby authorized to
borrow, in the name and on behalf of the Corporation, such amounts permitted or
provided to be borrowed by the Corporation pursuant to the Amendment; the act
of such borrowing and the execution and the delivery of any notes evidencing
such borrowing to be conclusive evidence of the approval thereof by such
officers and this board.

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     FURTHER RESOLVED, that the secretary of this Corporation is hereby directed
to file with the official records of this Corporation the forms of the
Documents.

     FURTHER RESOLVED, that the president, any vice-president or the secretary
of this Corporation be and each of them, acting alone, is hereby authorized to
certify and deliver to Lender a true copy of the foregoing resolutions.

     This Unanimous Consent of Directors may be executed in one or more
counterparts, each of which shall be deemed to be an original, and all of which
taken together shall constitute one and the same document.

     Dated at Milwaukee, Wisconsin as of October 10, 2001.


/s/ John C. Koss                /s/ Michael J. Koss
----------------------          ----------------------
John C. Koss                    Michael J. Koss


/s/ Laurence S. Matson          /s/ John J. Stollenwerk
----------------------          ----------------------
Laurence S. Matson              John J. Stollenwerk


/s/ Martin F. Stein             /s/ Victor L. Hunter
----------------------          ----------------------
Martin F. Stein                 Victor L. Hunter


/s/ Thomas L. Doerr
----------------------
Thomas L. Doerr


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