Crown Macro-Tech Schema & Bias

[audiotimo]

Hello,

I fixing a Crown Audio Macro-Tech 601 Amp.

Multiple problems here. Firstly, I have replaced 2 of the 4 main transistors of the right channel to get it working, and it works fine.

Now, the left channel then... it works, but distorts really easily.
I have a service manual with some tests to be run. The second test to measure bias already fails. There are 2 points to measure and adjust the bias and they are both way off the limits.

Im strugling to find a schema for this amp, and thus it's quite hard to continue the investigation.

Anyone, any tips where to find the schema or experiences what could be wrong?

Thanks regs Timo from Finland

 

[JonSnell Electronic]

It is similar to the 1201
Crown Diagrams, Schematics and Service Manuals for FREE
Have a look and download whatever you require.

 

[thejohn]

If the output transistors were blown, chances are the drivers, pre-drivers and bias transistors may also be blown. Also check the bias diodes and emitter resistors.

If I have the board out I usually replace most of the components. They're all cheap compared to the labour.

If you swap the output boards over you can isolate the fault to the output board or main board.

 

[audiotimo]

Thanks! Got the schema, and I'll continue wit these tips

 

[sherwin rambally]

crown macrotech 3600vz

can somone please explain me the full way to set the bias on crown 3600 vz.. what voltage should i have across R02... what voltage i should have across R21 ??

 

[PRR]

See the manual, page 4-1.

crown ma 3600vz service manual Download page :: Schematics Unlimited