Crate Powerblock 150 too low volume

[camarada78]

Hello,

I have a Crate Powerblock 150 on the bench right now.

It has very low volume, although everything seems to work.

The SMSP is giving the +-25v it should but still the volume is too low. This amp used to be a beast in terms of loudness.

It uses a tda8920th that is appears to be ok.

Am I missing something? What could make this amp work but with low volume instead?

The pots appear to be ok too. Opamps usually don't pass audio when they fail, never got one that pass but with low volume.

Weird.

Thanks in advance for the help

Have a good day

 

[abbey road d enfer]

Hello,

I have a Crate Powerblock 150 on the bench right now.

It has very low volume, although everything seems to work.

The SMSP is giving the +-25v it should but still the volume is too low. This amp used to be a beast in terms of loudness.

It uses a tda8920th that is appears to be ok.

Am I missing something? What could make this amp work but with low volume instead?

The pots appear to be ok too. Opamps usually don't pass audio when they fail, never got one that pass but with low volume.

Weird.

Thanks in advance for the help

Have a good day

You must trace the signal from the input to each subsequent stage. You will then see where signal is lost. You need a proper schemo to do so.

 

[JohnRoberts]

+1  the problem could be as simple as a bad connection, or dirty switch... I am not familiar with that model but if old enough, it may have a tired electrolytic cap.

Carefully with one hand in your pocket... probe around inside with power on... using a non-conductive probe. Sometimes by tapping around inside you can identify intermittent connections.

JR