I read in sci.electronics.design that Pooh Bear
wrote (in
) about 'Reducing hiss by changing
op-amps ?', on Tue, 22 Mar 2005:

The 072's not really that quiet by modern standards, John.

Of course, but it's better than the 4558. And you aren't in favour of
going to extremes:

QUOTE
If you want to experiment a bit, you might get a few LT1124CN8 dual
opamps to try as replacements for the 4558 types. They have make
about half the noise of the 4558.

NE5532s will do the job for a fraction of the price of the Linear
Technology part. Indeed, if you're having noise problems using 5532s -
something is seriously adrift !
ENDQUOTE

I get the impression that you always want the last word. If so, go play
with Brasfield.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk