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                                                                    EXHIBIT 10.1

                      ADVANCED LIGHTING TECHNOLOGIES, INC.
                                32000 Aurora Road
                                Solon, Ohio 44139

                                                        As of September 15, 2004

WELLS FARGO FOOTHILL, INC., as Agent and Lender
One Boston Place, 18th Floor
Boston, Massachusetts 02108

                         Re: Amendment to Loan Agreement

Ladies and Gentlemen:

      Wells Fargo Foothill, Inc., as Arranger and Administrative Agent
("Agent"), the lenders ("Lenders") from time to time parties to the Loan
Agreement (as defined below), and Advanced Lighting Technologies, Inc., an Ohio
corporation ("Parent") and each of Parent's Subsidiaries identified as a
borrower on the signature pages hereof (such Subsidiaries, together with Parent,
are referred to hereafter each individually as a "Borrower", and individually
and collectively, jointly and severally, as "Borrowers") have entered into
certain financing arrangements pursuant to the Amended and Restated Loan and
Security Agreement dated as of December 10, 2003, among Agent, Lenders,
Borrowers and the other Loan Parties (as the same now exists or may hereafter be
amended, modified, supplemented, extended, renewed, restated or replaced, the
"Loan Agreement"), and all other Loan Documents at any time executed and/or
delivered in connection therewith or related thereto. All capitalized terms used
herein shall have the meaning assigned thereto in the Loan Agreement, unless
otherwise defined herein.

      Borrowers and the other Loan Parties have requested that the Agent amend
the financial covenants contained in Section 7.20 of the Loan Agreement. Agent
has agreed to amend the financial covenants contained in Section 7.20 of the
Loan Agreement subject to the terms and provisions hereof.

      In consideration of the foregoing, and other good and valuable
consideration, Agent, Lenders, Borrowers and the other Loan Parties hereby agree
as follows:

      1. Amendment. As of the effective date of this Amendment, Section 7.20 of
the Loan Agreement is hereby amended and restated in its entirety as follows:

      "FINANCIAL COVENANTS.

      (a)   MINIMUM ADJUSTED EBITDA. Failure to maintain Adjusted EBITDA,
            calculated on a rolling twelve (12) month basis, measured on a
            fiscal quarter-end basis, of not less than the required amount set
            forth below for the applicable date set forth opposite thereto:

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<TABLE>
<CAPTION>
Applicable Amount                               Applicable Date
-----------------                             ------------------
<S>                                           <C>
   $20,000,000                                September 30, 2004
   $19,000,000                                December 31, 2004
   $20,000,000                                March 31, 2005
   $20,000,000                                June 30, 2005, and
</TABLE>

      as of the last day of each fiscal quarter thereafter, Adjusted EBITDA,
      calculated on a rolling twelve (12) month basis, shall not be less than an
      amount equal to eighty percent (80%) multiplied by Adjusted EBITDA as of
      such date as set forth in the then current Projections submitted by
      Borrowers and accepted by Agent in its Permitted Discretion, provided
      that, notwithstanding the foregoing, at no time after June 30, 2005 shall
      Adjusted EBITDA be less than $19,000,000.

      (b) CAPITAL EXPENDITURES. Make Capital Expenditures in fiscal year ending
      June 30, 2005 in an amount in excess of $7,250,000, and as of the last day
      of each fiscal year thereafter, Capital Expenditures shall not be greater
      than an amount equal to one hundred twenty percent (120%) multiplied by
      Capital Expenditures as of such date as set forth in the then current
      Projections submitted by Borrowers and accepted by Agent in its Permitted
      Discretion; provided, however, that for the purpose of this paragraph,
      Capital Expenditures shall not include the purchase of the DSI facility
      contemplated by Subsection 7(g) or any acquisition by UK Borrower, in each
      case, on terms approved by Agent in its Permitted Discretion."

      2. Effect of this Agreement. Except as specifically set forth herein, no
other changes or modifications to the Loan Agreement are intended or implied,
and, in all other respects, the Loan Agreement shall continue to remain in full
force and effect in accordance with its terms as of the date hereof. Except as
specifically set forth herein, nothing contained herein shall evidence a waiver
or amendment by the Agent or Lenders of any other provision of the Loan
Agreement nor shall anything contained herein be construed as a consent by the
Agent or Lenders to any transaction other than those specifically consented to
herein.

      3. Representations, Warranties and Covenants. In addition to the
continuing representations, warranties and covenants heretofore or hereafter
made by Borrowers to Agent or Lenders pursuant to the Loan Agreement and the
other Loan Documents, Borrowers hereby represent, warrant and covenant with and
to Agent and Lenders as follows (which representations, warranties and covenants
are continuing and shall survive the execution and delivery hereof and shall be
incorporated into and made a part of the Loan Documents):

            (a) No Event of Default or act, condition or event, which with
notice or passage of time or both, would constitute an Event of Default, exists
on the date of this letter agreement.

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            (b) This letter agreement has been duly executed and delivered by
Borrowers and the other Loan Parties and is in full force and effect as of the
date hereof, and the agreements and obligations of Borrowers and the other Loan
Parties contained herein constitute their respective legal, valid and binding
obligations enforceable against each in accordance with the terms hereof.

      4. Condition Precedent. This letter agreement shall not be effective
unless and until Agent shall have received an original hereof, in form and
substance satisfactory to Agent, duly executed and delivered by all Borrowers
and other Loan Parties.

      5. Binding Effect. The terms and provisions of this agreement shall be for
the benefit of the parties hereto and their respective successors and assigns;
no other person, firm, entity or corporation shall have any right, benefit or
interest under this agreement.

      6. Counterparts. This letter agreement may be signed in counterparts, each
of which shall be an original and all of which taken together constitute one
agreement. In making proof of this letter agreement, it shall not be necessary
to produce or account for more than one counterpart signed by the party to be
charged. Delivery of an executed counterpart of this letter agreement by
telefacsimile shall have the same force and effect as the delivery of an
original executed counterpart of this letter agreement. Any party delivering an
executed counterpart of this letter agreement by telefacsimile shall also
deliver an original executed counterpart, but the failure to do so shall not
affect the validity, enforceability or binding effect of this letter agreement.

      7. Further Assurances. The parties hereto shall execute and deliver such
additional documents and take such additional actions as may be necessary or
desirable to effectuate the provisions and purposes of this letter agreement.

      8. Governing Law. The validity, interpretation and enforcement of this
letter agreement and any dispute arising out of the relationship between the
parties hereto, whether in contract, tort, equity or otherwise, shall be
governed by the internal laws of the state of New York (without giving effect to
principles of conflicts of law).

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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      9. Entire Agreement. This letter agreement sets forth the entire agreement
and understanding of the parties with respect to the matters set forth herein.
This letter agreement cannot be changed, modified, amended or terminated except
in a writing executed by the party to be charged.

                               Very truly yours,

                            ADVANCED LIGHTING TECHNOLOGIES, INC., an
                            Ohio corporation, as a Borrower and a Loan Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President and
                                Chief Accounting Officer

                            APL ENGINEERED MATERIALS, INC.,
                            an Illinois corporation, as a Borrower and a Loan
                            Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President

                            VENTURE LIGHTING INTERNATIONAL, INC., an
                            Ohio corporation, as a Borrower and a Loan Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President

                            BALLASTRONIX (DELAWARE), INC.,
                            a Delaware corporation, as a Borrower and a Loan
                            Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President

                       [SIGNATURES CONTINUED ON NEXT PAGE]

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                    [SIGNATURES CONTINUED FROM PREVIOUS PAGE]

                            LIGHTING RESOURCES INTERNATIONAL, INC.,
                            an Ohio corporation, as a Borrower and a Loan Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President

                            DEPOSITION SCIENCES, INC.,
                            an Ohio corporation, as a Borrower and a Loan Party

                            By:   /s/ Christopher F. Zerull
                                ------------------------------------------------

                            Name: Christopher F. Zerull
                            Title: Vice President

                            VENTURE LIGHTING POWER SYSTEMS, NORTH AMERICA INC.,
                            a Nova Scotia corporation, as a Loan Party

                            By:   /s/ R.G. Douglas Oulton
                                ------------------------------------------------

                            Name: R.G. Douglas Oulton
                            Title: Vice President

                            PARRY POWER SYSTEMS LIMITED,
                            a corporation organized under the laws of the United
                            Kingdom, as a Loan Party

                            By:   /s/ Sabu Krishnan
                                ------------------------------------------------

                            Name: Sabu Krishnan
                            Title: Director

                       [SIGNATURES CONTINUED ON NEXT PAGE]

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                    [SIGNATURES CONTINUED FROM PREVIOUS PAGE]

                            VENTURE LIGHTING EUROPE LTD.,
                            a corporation organized under the laws of the United
                            Kingdom, as a Loan Party

                            By:   /s/ Sabu Krishnan
                                ------------------------------------------------

                            Name: Sabu Krishnan
                            Title: Director

ACKNOWLEDGED AND AGREED:

WELLS FARGO FOOTHILL, INC.,
a California corporation, as Agent and as a Lender

By:   /s/ John T. Leonard
    ----------------------------------------------

Name: John T. Leonard
Title: Vice President

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