• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

What does a bad capacitor sound like?

#2
My "hierarchy of suspicion" for instruments that suddenly get scratchy or have output issues is essentially jack, switches, pots, bad solder joint.

Does the issue come and go, or is it there all the time?
 
#3
Yeah this has happened to me on very old instruments. Replaced a pot and soldered the crusty old tone pot capacitor back in, and it can make noise. But it's still more likely the pot if you haven't replaced that yet. They're five bucks and carry them at all guitar shops.
 
#4
Paul Szegedin said:
Yeah this has happened to me on very old instruments. Replaced a pot and soldered the crusty old tone pot capacitor back in, and it can make noise. But it's still more likely the pot if you haven't replaced that yet. They're five bucks and carry them at all guitar shops.
Click to expand...
Too bad Radio shack isn't around selling eletronic equipment instead of Sprint Phones. Guitar stores really overprice their caps/resistors, but what can you do.
 
#5
Ferniff said:
Too bad Radio shack isn't around selling eletronic equipment instead of Sprint Phones. Guitar stores really overprice their caps/resistors, but what can you do.
Click to expand...
Yeah I miss radio shack for that. But there's not enough demand, even in big cities. To replace a tone cap, you have to order one from mouser and by the time you pay shipping, you're $15 in for a capacitor and waiting a week. :meh:
 
#6
You might be able to narrow it down by jiggling the plug in the output jack and jiggling and turning all the knobs. (Best case, it might be one of the pots and it might clear up with a quick cleaning.) Also visually check for sloppy connections in the wiring.
Redoing the whole harness on a standard passive bass usually isn't a big deal. IME it's pretty much a necessity for the sake of dependability when an instrument has budget components.
 
Last edited:
  • Like
Reactions: Rabidhamster
#7
Ferniff said:
Too bad Radio shack isn't around selling eletronic equipment instead of Sprint Phones. Guitar stores really overprice their caps/resistors, but what can you do.
Click to expand...
Paul Szegedin said:
Yeah I miss radio shack for that. But there's not enough demand, even in big cities. To replace a tone cap, you have to order one from mouser and by the time you pay shipping, you're $15 in for a capacitor and waiting a week. :meh:
Click to expand...
Sometimes...
Tone capacitors....one more time
 
#9
Standalone said:
My Ibanez EX404 has a sort of hairy crackle happening. It didn’t make the cut in the studio last night. Is this likely to be the cap? A bad pot?

I can’t imagine that it’s the pickup, but I don’t know the failure mode of pickups…
Click to expand...
Probably just a bad connection on the Jack, but your description is somewhat vague. What has you suspect the cap? I can’t think of an instance a cap could cause what you briefly described. More info and sound clips would be useful if you’re attempting to troubleshoot.
 
#10
Standalone said:
My Ibanez EX404 has a sort of hairy crackle happening. It didn’t make the cut in the studio last night. Is this likely to be the cap? A bad pot?

I can’t imagine that it’s the pickup, but I don’t know the failure mode of pickups…
Click to expand...
It's only the pot if it happens when you turn it.

If it's constant, it's either the cable or the jack
 
  • Like
Reactions: Aqualung60
#13
I can’t guarantee that you capacitor isn’t bad, but if I bet $10 that it isn’t, and did that bet 100 times on problems with the description you gave, I’d make at least $950.
 
#15
fdeck said:
In my years of fixing gear, almost all "electronic" problems turn out to be something mechanical. So I would look at cable, pots, jack. Not universally, but bad caps show their badness by how they behave under DC voltage, which is absent in a passive bass.
Click to expand...
I was about to say pretty much the same thing. Also, an audio sample would go a long way in helping to identify the problem. The order I would troubleshoot this:
1. Try another cable (which I consider to be the weakest link and the quickest to check).
2. This can be difficult on some instruments. With the wiring exposed and the instrument plugged in, try to replicate the sound. Like mentioned earlier, you may be able to find the root of the problem by probing around. It is very true that more than likely it is a mechanical problem.
 
#16
Thanks for your responses.

It’s a hairy crackly sound when playing — very even and not associated with motion very strange distortion. The bass plays… but in the studio the sound I was hearing through the amp was clearer. I switched basses and it was gone….

I have vintage audio gear and amps and caps do have a crackle to them that seems in the same neighborhood.

This is a bass that came to me de fretted and in rough shape. Who knows
 
#19
JeezyMcNuggles said:
It's only the pot if it happens when you turn it.

If it's constant, it's either the cable or the jack
Click to expand...
Yeah so just to clarify, it’s not happening with turning the pots. It’s not the usual jack issue that can be motion related, and tends to not be as subtle a sound - like a distorted hiss that is envelope related - it tracks with the sound of the note.

I know that cable and jack issues often masquerade as electronics. I switched basses, same cable, and life was good.
 

Latest posts

Top Bottom
Back