[sdiy] The sound of various Op-Amps

[Oakley Sound]

> I've found the OP275 chips to be quite nice in audio paths.

I concur.

But try this one at home kids: build a voltage follower with 10K input
resistance and a 10K resistor in the feedback path. Usual trick to keep
input impedances similar to reduce affects of bias currents and possibly
phase reversal if your lucky. And viola, the OP275 honks in the MHz. Now
I know unity gain is always going to push the limits of stability thanks
to that oh so naughty phase response, but that was a suprise. Perhaps I
should re-read the datasheet again. Remove the feedback resistor and all
is well...

For audio only the ye olde 5532 and using low value resistances the 5532
is better sounding to my ears than the OP275. A lot cheaper too. I also
rather like the LF412 for general purpose audio and CV use.

Regards,

Tony Allgood                       Penrith, Cumbria, England

Oakley Sound Systems                   www.oakleysound.co.uk
Modular Synthesisers      www.oakleysound.co.uk/projects.htm