Electrolytic caps: low ESR, audio signal, and...

[JackSkellington]

Hello, everybody.
Looking at the electrolytics caps I'm using Panasonic or another cheaper brand with a low ESR for the power supply parts. Panasonic has the FC series, that is ok, and has FM series, that even better. I used to buy both.
For audio signal I use Nichicon or Elna, specific audio signal series.

Here's the thing: some circuits (FET based, for example) have some large electrolytic caps going to the ground. It's not power supply, and not even a coupling cap. What kind of cap I should use for it? Low ESR or Audio Signal?

Thanks!

[WormBoy]

You mean the bypass cap you can find on the FET's source, or emitter of a BJT, in some circuits? I would normally try to use an 'audio grade' electrolytic there, since it is involved in frequency shaping. I highly doubt that it would make any difference what electrolytic you use in that position. But, for me, it's part of the fun of DIY to select the components that give me the greatest building joy .

[madbean]

Yeah I agree with WormBoy. A plain electrolytic for a bypass cap is fine. Save your "audio grade" style caps for coupling capacitors used in the audio signal path. If you are buying audio grade caps in large quantities, sure. But I wouldn't worry about feeling obligated to use those in places where they are not likely to make a difference.

[JackSkellington]

Thanks guys.
Indeed, WormBoy, I was thinking about that bypass cap in the circuits you told.

I'll do like that, If I have to buy a bunch of "audio grade" I could use those, else I'll use what I have in my stock.