Static like sound

[bassman7777]

Hi team...
I have an Ampeg B112 that has a slight "static like" sound that shows up on held notes. Hard to describe...not a crackle, but like static. Not very loud, but enough that you can hear it. Now, this is just a practice amp, but I wanted to give it to one of my students. I would rather not with that annoying sound. I tried swapping out the speaker. No change, it seems electronic. Any ideas? Probably not worth putting much money into it because it would probably cost more to have someone to look at it than what it is worth. Any ideas, input or suggestions?
Thanks

 

[agedhorse]

If there’s an effects loop in the amp, try jumping from the send to the return with a short shielded cable.

 

[seamonkey]

If it's "hard to describe" then post a recording.
Some people around here (not me) can tell a lot by how it sounds.

 

[S-Bigbottom]

Is your bass active?
A battery going low can produce this, especially on low notes.

 

[bassman7777]

Is your bass active?
A battery going low can produce this, especially on low notes.

Passive bass, does not do it through headphones, n o send/receive loop. Maybe a capacitor? AS I mentioned, probably cost more to fix than to replace. I would love to give it to one of my students. Otherwise, it will be a big and heavy headphone amp.

 

[ddnidd1]

You could probably buy a used amp for what a repair would cost.

 

[Hoochie Coochie Man]

I would begin troubleshooting this problem by cleaning any jacks, and then doing an inspection under good lighting, and magnification of all solder joints on the circuit board. Look for cracked joints where pots, and jacks are soldered. Also look for joints that may not have been properly soldered to begin with. A good soldier joint should be shiny. You could also, just try to reflow solder joints at likely problem spots. Use a soldering iron with an ESD safe, (grounded) tip if you try this. Inspect both sides of the circuit board. Also reseat any plug-in connectors you find.

These are all mostly long-shot things to try, but if you can do them yourself, they are at least no cost.

 

[agedhorse]

Passive bass, does not do it through headphones, n o send/receive loop. Maybe a capacitor? AS I mentioned, probably cost more to fix than to replace. I would love to give it to one of my students. Otherwise, it will be a big and heavy headphone amp.

The classic “bad cap” myth is right at the bottom of the list.

 

[agedhorse]

I would begin troubleshooting this problem by cleaning any jacks, and then doing an inspection under good lighting, and magnification of all solder joints on the circuit board. Look for cracked joints where pots, and jacks are soldered. Also look for joints that may not have been properly soldered to begin with. A good soldier joint should be shiny. You could also, just try to reflow solder joints at likely problem spots. Use a soldering iron with an ESD safe, (grounded) tip if you try this. Inspect both sides of the circuit board. Also reseat any plug-in connectors you find.

These are all mostly long-shot things to try, but if you can do them yourself, they are at least no cost.

Only recommend this if the person understands proper safety precautions when working on electronics. The guess about a bad cap suggests otherwise.

 

[Discount Bassy]

Start with the easy stuff. Twist your knobs (non-sexual) while playing a note. Check the cables and visually inspect the solder connections. Plug and unplug the cables from the pertinent jacks a few times to knock any crud loose. Wiggle the cables while ringing a note. Flex the cables while ringing a note. Don't take anything apart based purely on speculation until you have a specific intent and reason to do so.

 

[Tommy Sparks]

I’ve had this with dirty pots on an amp that sat awhile. Twist the heck out of the pots as suggested above. Also it’s free, good luck and
Try to refrain from spraying anything in em.