Marshal amp is being quiet

[stolenband]

Hey guys. Got something for you all.

I just got a marshall bass 12 amp from a goodwill for 25.00 dollars. And it is being quiet. It is not even competing with an acoustic. Is there anything that i need to check on it?? it does also have a gain nob that must be on 4 for it to work. anyone have any fixes?? I want to use the amp, but it is not working for me. Thanks. its hard to find anything on the net.

[geraldfryjr]

WHAT IS THE MODEL NUMBER?

[stolenband]

t27329 I think. That is what is stamped to the front

[Nigel Goodwin]

Originally Posted by stolenband

t27329 I think. That is what is stamped to the front

That doesn't sound like a Marshall number?, try looking on the back.

[teemuk]

I think the only Marshall Bass 12 would be 5501.

Is there anything that i need to check on it?? it does also have a gain nob that must be on 4 for it to work. anyone have any fixes??

Plenty, for starters:
- Contact intermittency? / condition of solder joints
- Potentiometer / jack corrosion and overall condition, use some contact cleaner
- Output transistors ok?

If these don't help start tracing signal from input towards output and see what stage fails to amplify or what stage causes too much attenuation.

[geraldfryjr]

Here is the schematic. jer


Need schematics: Marshall 5501 Bass 12-amplifier - TalkBass Forums