[sdiy] (Electrolytic) Capacitors in audio coupling

[René Schmitz]

Seb Francis schrieb:

> I think I do need the values that I'm using as they are matched to the
> requirements of the input and output stages of an audio CODEC.  The
> other place is the input to a THAT VCA, and again I've gone with the
> values the datasheet has suggested.

Well occasionally it is needed to apply healthy amounts of criticism to
datasheet suggestions. 1/(2 pi R C) is your friend here. While a larger
cap gets you to lower corner frequencies, it also takes longer to charge
up the cap to the quiescent condition during turn on or under overdrive
conditions.
I think that in all cases you could get away with smaller values, except
for the cap at the input buffer directly before the codecs input. And I
say that only, because I haven't bothered to check its datasheet.

> This sounds interesting, so maybe parallel a C0G ceramic?  I could lay
> an extra footprint to be able to try this out.  Would you suggest any
> particular values?

I'd start with something like 1/10 or 1/100 of the larger cap.

Cheers,
  René

-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159