Exhibit 10.5.1

[Execution
Version]

AMENDMENT NO. 2 AND WAIVER TO LOAN AND SECURITY AGREEMENT

AMENDMENT NO. 2 AND WAIVER TO LOAN AND SECURITY AGREEMENT ("Amendment No. 2"), dated April 16, 2004, by and among LOUD Technologies Inc., a
Washington corporation formerly known as Mackie Designs Inc. ("US Borrower"), Mackie Designs UK Plc, a company incorporated under the laws of England and Wales with registration number 02506901
("UK Borrower", and together with US Borrower, each individually a "Borrower" and collectively, "Borrowers"), Mackie Designs Inc., a Washington corporation, formerly known as Mackie Designs
Manufacturing, Inc.("Mackie"), SIA Software Company, Inc., a New York corporation ("SIA") Mackie Investment Co., a Washington corporation ("Mackie Investment", and together with Mackie
Manufacturing and SIA, each individually a "Guarantor" and collectively, "Guarantors"), Congress Financial Corporation (Florida), in its capacity as agent pursuant to the Loan Agreement (as
hereinafter defined) acting for and on behalf of the parties thereto as lenders (in such capacity, "Agent"), and the parties to the Loan Agreement as lenders (individually, each a "Lender" and
collectively, "Lenders").

W I T N E S S E T H:

WHEREAS,
Agent, Borrowers and Guarantors have entered into financing arrangements pursuant to which Agent and Lenders have made and may make loans and advances to Borrowers as set forth
in the Loan and Security Agreement, dated March 31, 2003, by and among Agent, Lenders, Borrowers and Guarantors as amended by Amendment No. 1 to Loan and Security Agreement dated
June 30, 2003 (as the same now exists or may hereafter be amended, modified, supplemented, extended, renewed, restated or replaced, the "Loan Agreement") and other agreements, documents and
instruments referred to therein or at any time executed and/or delivered in connection therewith or related thereto (all of the foregoing, together with the Loan Agreement, as the same now exist or
may hereafter be amended, modified, supplemented, extended, renewed, restated or replaced, being collectively referred to herein as the "Financing Agreements");

WHEREAS,
Agent, Lenders, Borrowers and Guarantors desire to amend certain covenants and make certain other amendments to the Loan Agreement;

WHEREAS,
by this Amendment No. 2, Agent, Lenders, Borrowers and Guarantors desire and intend to evidence such amendment;

NOW
THEREFORE, in consideration of the foregoing and the mutual agreements and covenants contained herein, the parties hereto agree as follows:

1.Definitions.



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2.Interest Rate.Section 1.69 of the Loan Agreement is hereby amended by deleting such Section in its
entirety and substituting the following therefor:

"1.69    "Interest
Rate" shall mean,



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3.Raw Material Availability.



4.     Term
Loans. Section 2.3 of the Loan Agreement is hereby amended by inserting the following immediately after the end of such Section:



5.EBITDA.Section 9.17 of the Loan Agreement is hereby amended by deleting such Section in its entirety
and substituting the following therefor:



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Period

Amount1/1/041/31/04

$
(1,333,000
)1/1/042/29/04

$
(1,748,000
)1/1/043/31/04

$
(3,651,000
)1/1/044/30/04

$
(3,304,000
)1/1/045/31/04

$
(2,119,000
)1/1/046/30/04

$
(877,000
)1/1/047/31/04

$
297,0001/1/048/31/04

$
861,0001/1/049/30/04

$
1,857,0001/1/0410/31/04

$
2,865,0001/1/0411/30/04

$
4,034,0001/1/0412/31/04

$
5,446,0003/31/043/31/05

$
9,769,0007/1/046/30/05

$
9,963,00010/1/049/30/05

$
9,867,000I/1/0412/31/05

$
8,907,000Each twelve-month period thereafter $8,907,000 ending on the last day of each calendar quarter

$
8,907,000


The
use of paretheses is this Section 9.17 is intended to reflect negative numbers."

6.Equipment Sales.Section 9.7(b)(ii) of the Loan Agreement is hereby amended by deleting such
Section in its entirety and replacing the following therefor:



7.Equipment Reserve.Within five (5) Business Days after Agent's receipt, on or after April 28,
2004, of an Acceptable Equipment Appraisal (as defined below), Agent shall reduce the Special Equipment Reserve by an amount equal to the difference (if positive) between
(a) eighty-five (85%) percent of the net orderly liquidation value of the Equipment as reflected in the Equipment appraisal most recently received by Agent pursuant to
Section 7.4 of the Loan Agreement and (b) the then aggregate outstanding principal amount of the Term Loans;provided, that, each of the
following conditions is satisfied:(i) as of the date of any such reduction and after giving effect thereto, no Default or Event
of Default shall have occurred and be continuing, (ii) Agent shall have received, on or after April 28, 2004, a written appraisal as to the Equipment in form, scope and methodology
acceptable to Agent by an appraiser acceptable to Agent, addressed to Agent and Lenders and upon which the Agent and Lenders are expressly permitted to rely (an "Acceptable Equipment Appraisal"), and
(iii) in no event shall the Special Equipment Reserve be reduced below zero; it being understood that the

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foregoing
shall in no way modify, limit or otherwise impair the ability of the Agent to establish other Reserves in accordance with the terms of the Loan Agreement.

8.     Waiver.



9.Amendment Fee.In addition to all other fees, charges, interest and expenses payable by Borrowers to Agent
and Lenders under the Loan Agreement and the other Financing Agreements, Borrowers shall pay to Agent for the account of Lenders, contemporaneously with the effectiveness of this Amendment, an
amendment fee in the amount of $50,000, which fee shall be fully earned and payable on the effective date hereof and may be charged to any loan account of Borrowers.

10.Additional Representations, Warranties and Covenants.Borrowers 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 the truth and accuracy of, or compliance with
each, together with the representations, warranties and covenants in the other Financing Agreements, being a continuing condition of the making of Loans by Lenders (or Agent on behalf of Lenders) to
Borrowers:



11.Conditions Precedent for Amendment.The amendments contained herein shall be effective upon Agent's receipt
of the following: (a) this Amendment No. 2, duly authorized, executed and delivered by Borrowers, Guarantors and Required Lenders, (b) an amendment to the Junior Loan Agreement,
in form and substance satisfactory to Agent (the "Junior Amendment") duly authorized, executed and delivered by the parties thereto and (c) evidence satisfactory to Agent that the Junior
Amendment is in full force and effect.

12.Effect of this Amendment.Except as modified pursuant hereto, no other changes or modifications to the
Financing Agreements are intended or implied, and in all other respects the Financing Agreements are hereby specifically ratified, restated and confirmed by all parties hereto as of the effective date
of this Amendment No. 2. To the extent of conflict between the terms of this Amendment No. 2 and the other Financing Agreements, the terms of this Amendment No. 2 shall control.

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13.Further Assurances.Borrowers and Guarantors shall execute and deliver such additional documents and take
such additional action as may be reasonably necessary or desirable to effectuate the provisions and purposes of this Amendment No. 2.

14.Governing Law.The validity, interpretation and enforcement of this Amendment No. 2 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 Florida (without giving effect to
principles of conflicts of laws).

15.Binding Effect.This Amendment No. 2 shall be binding upon and inure to the benefit of each of the
parties hereto and their respective successors and assigns.

16.Headings.The headings listed herein are for convenience only and do not constitute matters to be construed
in interpreting this Amendment No. 2.

17.Counterparts.This Amendment No. 2 may be executed in any number of counterparts, but all of such
counterparts shall together constitute but one and the same agreement. In making proof of this Amendment No. 2, it shall not be necessary to produce or account for more than one counterpart
thereof signed by each of the parties hereto. This Amendment No. 2 may be executed and delivered by telecopier with the same force and effect as if it were a manually executed and delivered
counterpart.

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 2 to be duly executed and delivered by their authorized officers as of the day and year first above written.

| |  | BORROWERS                                                              
| |  | -----------------------------------------------------------------------
| |  | LOUD TECHNOLOGIES INC., formerly known as Mackie Designs Inc.          
| |  | By:                                                                    
| |  | Title:                                                                 
| |  | MACKIE DESIGNS UK PLC                                                  
| |  | By:                                                                    
| |  | Title:                                                                 
| |  | By:                                                                    
| |  | Title:                                                                 
| |  | GUARANTORS                                                             
| |  | MACKIE DESIGNS INC., formerly known as Mackie Designs Manufacturin Inc.
| |  | By:                                                                    
| |  | Title:                                                                 
| |  | SIA SOFTWARE COMP , INC.                                               
| |  | By:                                                                    
| |  | Title:                                                                 

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| |  | MACKIE INVESTMENT CO.                             
| |  | --------------------------------------------------
| |  | By:                                               
| |  |                                                   
| |  | Title:                                            
| |  | AGENT                                             
| |  | CONGRESS FINANCIAL CORPORATION (FLORIDA), as Agent
| |  | By:                                               
| |  | Title:                                            
| |  | LENDER                                            
| |  | CONGRESS FINANCIAL CORPORATION (FLORIDA)          
| |  | By:                                               
| |  | Title:                                            

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EXHIBIT AProjected EBITDA for 2004

LOUD Technologies
Consolidated Statements
of Operations

FY 2004
ForecastEBITDANet Income (Loss)

(1,486
)Income Taxes

Depreciation and Amortization

5,110Interest Expense (net)

2,782Management Fee

Adjusted EBITDACongress

6,407


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EXHIBIT BProjected EBITDA for 2005

LOUD Technologies
Consolidated Statements
of Operations

FY 2005
ForecastEBITDANet Income (Loss)

2,430Income Taxes

Depreciation and Amortization

5,110Interest Expense (net)

2,939Management Fee

Adjusted EBITDACongress

10,479


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SCHEDULE 1

1.     Event
of Default under Section 10.1(a)(iii) of the Loan Agreement arising from the failure of US Borrower and its Subsidiaries to comply with
Section 9.17 of the Loan Agreement for the period ending on each of June 30, 2003, September 30, 2003, December 31, 2003.

2.     Event
of Default under Section 10.1(a)(iii) of the Loan Agreement arising from failure of Borrowers and Guarantors to give timely notice to Agent of the
name change of (a) US Borrower from Mackie Designs Inc. to LOUD Technologies Inc. and (b) Mackie from Mackie Designs Manufacturing, Inc. to Mackie
Designs Inc., each as required under Section 9.1(b) of the Loan Agreement.

3.     Event
of Default under Section 10.1(a)(iii) of the Loan Agreement as a result of the failure of Borrowers and Guarantors to promptly notify Agent in writing
of the occurrence of the Events of Default set forth in Sections 1 and 2 above as required Section 9.6(b)(vi) of the Loan Agreement.

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