John Woodgate wrote:

I read in sci.electronics.design that Pooh Bear rabbitsfriendsandrelati
wrote (in ) about
'Reducing hiss by changing op-amps ?', on Sat, 19 Mar 2005:

Simplest substitution option is the very much better 4560 also from JRC.

You might with advantage suggest which ones are likely to benefit most
from substitution. I can't decipher the schematic clearly enough to do
it.

Since the 4558 is a poor performer in just about every respect ( not much
better than a dual 741 ) , I'd suggest global replacement.

It's true that certain stages might benefit from replacement with quieter
parts ( classically the bus mix amps for example ) but the 4560 is a good
start point. I'd suggest 4580s too but they use twice as much supply current.



Graham