Shame you can't point us to the circuits. Even with your extra notes,
above, there are still many questions arising - not least if your notes
are incorrect. (It does happen!)
Most Op Amps applications are inherently PSU-ripple insensitive.
They are a design from Elliot Sound Products. But the published schematic
doesn't show the supply rail side of the design. You have to buy the PCB
to see it.
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*IF A TURTLE DOESN'T HAVE A SHELL, IS HE HOMELESS OR NAKED?
Dave Plowman
London SW
To e-mail, change noise into sound.