Peavey Firebass 700 Distorting

[TNMoney]

Hey friends

I’ve had a Firebass 700 that has served me well for the past four years. It’s powering an Avatar 4 by 10 cab at 4 oms. Recently I’m getting some weird distorted tones out of it, almost like the sound an onboard preamp might get with a dying battery or like sputtering type fuzz. It’s most pronounced on the e string, and I feel like volume levels may have dropped as well.

Ive tested with multiple basses (all passive) and when I swapped out for a different head, there’s no issues, so there’s no signal chain problem. EQ is set flat and changing gain settings doesn’t seem to make much difference distortion wise. Before this I’ve been able to push it pretty hard with no fartiness or ugly sounding distortion. Definitely has not been abused.

Any ideas on what may be going on or simple things to try to remedy? I did vacuum the garage recently and maybe more dust than usual was floating around.

 

[agedhorse]

IIRC, that amp has an effects loop. Try connecting a short cable between the effects send and return and see if the amp returns to normal.

 

[TNMoney]

IIRC, that amp has an effects loop. Try connecting a short cable between the effects send and return and see if the amp returns to normal.

Thank you for the suggestion. I just tried and I did not have any luck unfortunately…

 

[agedhorse]

There are so many possibilities (most require test equipment to diagnose PROPERLY) that I would suggest finding a Peavey authorized service center that has experience with these amps. While there are some mechanical things that can cause these issues, there are a lot more electronic causes and there's some tricky circuitry in the power amp management that's more advanced than the basic older school architecture.

 

[TNMoney]

There are so many possibilities (most require test equipment to diagnose PROPERLY) that I would suggest finding a Peavey authorized service center that has experience with these amps. While there are some mechanical things that can cause these issues, there are a lot more electronic causes and there's some tricky circuitry in the power amp management that's more advanced than the basic older school architecture.

Thanks so much for you input! That’s probably going to be my next step.