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                                                                   Exhibit 10.41

                               SUB-LEASE AGREEMENT


         THIS SUB-LEASE AGREEMENT, made and entered into this 3rd day of January
2001, by and between Van's Delivery Service, Inc. whose address 2280 Turner NW,
Grand Rapids, MI 49504 (hereinafter referred to as "Sub-Lessor"), and Rockford
Acoustic Designs, Inc. of 609 Myrtle NW, Grand Rapids, MI 49504 (hereinafter
referred to as "Sub-Lessee").

                              W I T N E S S E T H:


         WHEREAS, Sub-Lessor is the Lessee of a certain building commonly known
as 2356 Turner NW, Grand Rapids, MI; and

         WHEREAS, Sub-Lessee wishes to Sub-Lease a portion of 2356 Turner from
Sub-Lessor and Sub-Lessee agree as follows:

         1. Sub-Lease of Premises. Sub-Lessor hereby agrees to Sub-Lease to
Sub-Lessee, and Sub-Lessee agrees to initially rent from Sub-Lessor,
approximately 45,000 square feet (herein referred to as the "Premises"), which
space is described and set forth in the outline and floor plan attached hereto
as Exhibit A. Sub-Lessee will increase its lease area annual by ("as agreed to
by both parties at least 60 days notice prior to the annual lease anniversary")
SF at the beginning of the second lease year up to 70,000 SF at the beginning of
the third lease year.

         2. Term. The term of this Sub-Lease shall commence not later than three
weeks after Sub-Lessor has substantially completed its work required for
Sub-Lessee's occupancy (estimated to be on or about March 1, 2001), and continue
for a period of 36 months.

         3. Rent. Sub-Lessee agrees to pay to Sub-Lessor as rental for the
Premises an annual rent of $146,250.00. This sum shall be payable in equal
monthly installments of $12,187.50, payable in advance on the first day of each
and every month at Sub-Lessor's address as set forth in the first paragraph
hereof. Fractional months, if any, shall be prorated to the date of occupancy as
described herein or the date of possession whichever is sooner. As Sub-Lessee
increases its space as provided for above, they will pay base rent for the
entire premises at a rate of $3.35 PSF during the second lease year, and at a
rate of $3.45 PSF during the third lease year. In the event Sub-Lessee desires
to extend this Sub-Lease beyond the three-year term, Sub-Lessor agrees to do so
provided that the rent and duration of any extension will be mutually agreed
upon prior to the commencement of such extension. Should Sub-Lessor not extend
its lease with the property owner, they will assist Sub-Lessee in negotiating
such extension with property owner.

         4. Refurbishing of Premises. Vans will install approximately 625 SF of
open office area, one additional restroom, a break area adjacent to the
office/restrooms, partitioning fence for the initial Sub-Lease area, access to
existing electronic security system, and 25-30 parking spaces. Rockford will
install any other improvements it may desire including electrical work, and pay
for future additions to or relocation of the partition fencing. Any required
re-striping of parking spaces to be Rockford's expense.
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         5. Sub-Lessee's Responsibilities. Sub-Lessee acknowledges and agrees
that it will be responsible for payment of its prorata share of utility cost of
$1,791 per month plus any amounts in excess of that amount, plus its telephone,
and any other fees incurred by reason of its use and occupancy of the Premises.
Sub-Lessee will also pay for its share of taxes, insurance and common area
operating expenses that will be billed annually. Costs for such taxes, insurance
and common area operating expenses in calendar year 2000 were estimated at $0.60
PSF.

         Sub-Lessee agrees to keep and maintain the Premises in good and
reasonable repair, Sub-Lessee is responsible for its own janitorial service, and
shall maintain said Premises in a neat and orderly fashion at all times.
Sub-Lessee shall immediately report to Sub-Lessor any defective condition found
or known outside of the Premises. Sub-Lessee shall be responsible for repair or
replacement of any damage caused by misuse or negligence of any of its
employees, agents, patients, guests or invitees. Sub-Lessee agrees to operate
its business to be at all times in compliance with all requirements made by any
public authority or insurance rating body with respect to the Premises and its
actions therein.

         6. Sub-Lessor's Responsibility. Through its original lease terms,
Sub-Lessor agrees to provide all general maintenance and upkeep of common areas
of the building, grounds, parking areas, etc., except as provided in Paragraph 5
above.

         7. Fixtures. Sub-Lessee may place on the premises and maintain for its
use during the term hereof, such movable fixtures as may be necessary and
convenient for the conduct of its business. Sub-Lessee may attach trade fixtures
to the Premises; provided that it shall restore the Premises to their original
condition upon any termination of this Sub-Lease Agreement, including repair of
any and all damage caused by the removal of fixtures, reasonable wear and tear
excepted. It is understood that all such fixtures shall remain the sole property
and possession of Sub-Lessee, and shall be removed at once prior to the
expiration or other termination of this Sub-Lease Agreement.

         8. Assignability and Subletting. Sub-Lessee shall not further sublet
the Premises or any portion thereof without the Sub-Lessor's consent, which
shall not be unreasonably withheld.

         9. Common Areas. Sub-Lessee's use and occupancy of the premises shall
include the right to use in common with other Sub-Lessees the common area,
parking areas, service roads, loading facilities, sidewalks and any other
facilities as may be designated from time to time by Sub-Lessor, subject to the
terms and conditions of this Agreement and reasonable rules and regulations for
the use thereof as prescribed from time to time by Sub-Lessor. All common areas
described above shall at all times be subject to the exclusive control and
management of Sub-Lessor and Sub-Lessor shall have the right, from time to time,
to establish, modify and enforce reasonable rules and regulations with respect
to all facilities and areas mentioned herein. Sub-Lessor shall have the right to
construct, maintain and operate lighting facilities in and on such areas, to
police the same, to change levels, locations and arrangements of parking areas
and other facilities herein, and to restrict parking by Sub-Lessee, its
employees, agents and invitees.

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         10. Fire or Destruction. If, during the term of this Sub-Lease the
Premises are more than 75% destroyed by fire, the elements or other casualty,
then this Sub-Lease Agreement shall terminate at the option of either party upon
written notice to the other, and rent shall be prorated to the date of
termination. During the time in which such repairs are being made, however, no
rent shall be payable except on a prorata basis for such part of the Premises as
may be used and occupied by Sub-Lessee.

         11. Insurance. Subject to reimbursement by Sub-Lessee as provided for
above, Sub-Lessor shall furnish fire and extended coverage insurance on the
Premises at its own expense. Sub-Lessee shall carry its own fire insurance
coverage with respect to the contents of the Premises and all of its personal
property and fixtures in or attached to the Premises. Sub-Lessee shall also
maintain adequate public liability insurance in amounts of not less than
$10,000/300,000, naming Sub-Lessor as an additional insured, and Sub-Lessee
shall furnish Sub-Lessor with a Certificate of Insurance evidencing such
insurance.

         All policies of insurance maintained by either of the parties shall
contain appropriate clauses or endorsements under which the insurer waives all
right or subrogation against the other party, its agents, employees, invitees
guests and licensees, with respect to losses payable under such policies. This
waiver of subrogation rights shall be valid and binding only in the event it is
recognized and accepted by the insurance companies under the policies carried on
the Premises, building and common areas.

         12. Taxes. Subject to reimbursement by Sub-Lessee as provided for
above, Sub-Lessor shall pay all real estate taxes and special assessments
attributable to the real estate upon which the Premises stand. Sub-Lessee shall
pay all personal property taxes on its property located on and in said Premises.

         13. Liability. Sub-Lessee agrees to indemnify and hold Sub-Lessor
harmless from any claims, damages, expenses, degrees, judgments, costs, etc.,
arising from or out of the negligence of Sub-Lessee, its employees, agents,
patients or invitees, for any injury occurring on the Premises. Sub-Lessor shall
be liable for its own negligence, or that of its servants, employees or agents,
provided that the notice provisions described in Paragraph 5 hereof have been
complied with. Failure by Sub-Lessee to promptly notify Sub-Lessor of any
defective condition(s) existing outside the Premises and/or of any injury and/or
damage occurring outside the Premises shall give Sub-Lessor the right to seek
indemnification from Sub-Lessee for any liability Sub-Lessor may occur.

         14. Condemnation. In the event all or any portion of the Premises shall
be taken or threatened to be taken through condemnation or the exercise of the
right of eminent domain, including any conveyance and grants in anticipation of,
or in lieu of such taking, thereby rendering the Premises unusable for the
purposes for which said Premises are hereunder Sub-Leased to Sub-Lessee, either
party hereto shall have the right to terminate this Sub-Lease, and each party
shall be entitled to its share of any award for such taking, based upon its
damages.

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         15. Right of Entry. Sub-Lessor, his agents or representatives, upon
notification (except in the event of an emergency), shall have the right to
enter the Premises, or any part thereof, at all reasonable times for the
purposes of examining the same.

         16. Sub-Lessor's Work. See # above

         17. Default. In the event there is any default by Sub-Lessee in the
payment of any monies herein agreed to be paid, and if such default shall
continue for a period of thirty (30) days after receipt of written notice of
same from Sub-Lessor, or if there is any default in the performance or
observance of any of the covenants or conditions of this Sub-Lease required to
be performed by Sub-Lessee within a like period after written notice of such
default delivered to Sub-Lessee by Sub-Lessor, Sub-Lessor shall have the right
to terminate this Sub-Lease and re-enter and take possession of the Premises. If
the default is of a covenant or condition not relating to the payment of monies,
and such default cannot reasonably be cured within the thirty (30) day period
described above, Sub-Lessee shall make a good faith effort to begin to cure the
same and the provisions herein for termination of this Sub-Lease shall abate so
long as Sub-Lessee continues to proceed to cure such default within a reasonable
time.

         18. Subordination. This Sub-Lease and Sub-Lessee's rights hereunder
shall at all times be subordinate to the original lease between the owner and
the Sub-Lessor,, and the lien of any mortgage now or hereafter, from time to
time, placed upon the Premises or the land and building of which the Premises
are a part and Sub-Lessee agrees to provide any such mortgage with a customary
Sub-Lessee's estoppel letter, from time to time, at the request of any such
mortgagee with respect to the status of this Sub-Lease or any collateral
assignment of this Sub-Lease and/or the rents hereunder which may be made by
Sub-Lessor to any such mortgagee as additional security for the indebtedness
secured by such mortgage; provided, however, that such subordination shall be
subject to the condition precedent that Sub-Lessee and any such mortgagee shall
have entered into a customary nondisturbance and attornment agreement concerning
the rights of Sub-Lessee and the mortgagee in the event of a default and
foreclosure. In the event the proceeds of casualty insurance or condemnation are
required by mortgagee to be applied to reduce the mortgage debt rather than to
restoration of the damaged or taken property, then this Sub-Lease shall
terminate and neither party shall have any further obligation to the other.

         19. Quiet Enjoyment. Sub-Lessor agrees that, conditioned upon the
prompt performance and observance by Sub-Lessee of all the terms, covenants and
conditions hereof required to be performed or observed by it, Sub-Lessee shall
at all times during the term of this Sub-Lease have peaceable and quiet
enjoyment and possession of the Premises.

         20. Notices. Any notice or demands required or allowed to be given
hereunder, shall be deemed given if delivered to the parties by U.S. Mail,
certified or registered, with return receipt requested by the giving party,
addressed to each of the parties at the addresses set forth in the first
paragraph of this Sub-Lease, or at such other address as either may indicate, in
writing, form time to time.

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         21. Amendment. This Sub-Lease Agreement may not be altered, changed or
amended in any way whatsoever, except in writing and executed by all parties
hereto.

         22. Severability. In the event any portion of this Sub-Lease shall be
deemed invalid or illegal, the remaining provisions shall remain in full force
and effect.

         23. Binding Effect. This Sub-Lease Agreement shall be binding upon, and
inure to the benefit of, the parties hereto and their respective successors and
assigns.

         24. Choice of Law. This Sub-Lease shall be subject to and construed in
accordance with the laws of the State of Michigan. Any dispute arising out of or
in any way related to the terms and provisions hereof, shall be litigated in
Kent County, MI.

         25. Captions. The captions and headings used herein are for the
convenient reference of the parties only, and shall not be used to in any way
limit, enlarge or interpret the meaning hereof.

         26. Brokerage Fees.


         27. Security Deposit. Lessee has paid to Lessor upon execution of this
Lease, the first month's rent of $12,187.50 and the sum of $12,187.50 as
security deposit for the performance of lessee's obligations hereunder,
including the payment of any rentals. In the event of a default by Lessee,
Lessor at its option may apply such part of the deposit as may be necessary to
cure the default, and if Lessor does so, Lessee shall upon demand redeposit with
Lessor an amount equal to that so applied so that Lessor will have the full
security deposit on hand at all times during the term of this Lease. Upon the
termination of this Lease, (provided that Lessee is not in default hereunder),
Lessor shall refund to Lessee any then remaining balance of the deposit without
interest. In the event of a sale of the land and building or leasing of the
building, of which the demised premises form a part, Lessor shall have the right
to transfer the deposit to the vendee or lessee and Lessor shall thereupon be
released by Lessee from liability for the return of such deposit; and Lessee
agrees to look to the new lessor solely for the return of said deposit; and it
is agreed that the provisions hereof shall apply to every transfer or assignment
made of deposit to a new lessor.

         IN WITNESS WHEREOF, the parties have executed this Sub-Lease Agreement
this 21st day of December, 2000.


 By:  /s/                                 By:  /s/
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WITNESS                                   WITNESS

 By:  /s/                                 By:  /s/
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