Peavey Basic 60 fuzz

[jphenix]

Hi all, new to the forum.
Have a 20-year old amp that is fuzzing out through the speaker but sounds fine through headphones. Tried both High and Low inputs. Changed out bass' active battery. Using new signal cable.
I appreciate any suggestions you might have.

 

[RickenBoogie]

Damaged speaker?

 

[thumpbass1]

I'm trying to remember the Basic 60 layout. You should have some sort of preamp in/ out jack. I'd start testing there, by seeing how it sounds running into the power amp section of another bass amp if you have access to another bass amp. From there you could have a problem in the power amp section, or the speaker itself might be the problem. I wish you luck.

 

[nashvillebill]

If the Basic 60 schematic is similar to the Keyboard 60 (and I believe it is), the headphone out is taken directly from the output to the speaker. The headphone jack just disconnects the speaker and puts a dropping resistor inline.

So if the output through the headphones is OK, then the rest of the amp is fine. Which leaves only one culprit: a bad speaker. Probably it's been driven too hard and the voice coil has melted a little and is rubbing, or the surround or spider has torn.