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[Haible Juergen]

	>>And third, havent Magnus told you that you
	>>"shall not" use Ne5532 in a vocoder, since BJ
	>>"made that mistake" many years ago, Jurgen? :-)
	>>They "oscillate" like hell!!! :-)
	>
	>I recognized that the NE5532 only oscillate when the output sees no
load.
	>When you add a load resistor to ground everthing works fine...

The NE5532 is a good affordable audio opamp - sort of "standard" even ?
It's true that it's more sensitive to oscillation / decoupling than a LF353
of TL072. I can tell, because I've used sockets for that whole bank of
whatever-it-might-be, and put in some fifty of these BiFET amps at first.
Even though their data sheets ask for individual decoupling of each IC,
the whole board would work with a couple of 10u tantal and another couple
of 100n ceramic. Not so the 5532. I put them in one by one, and checked for
oscillations after each one. Turned out that I needed approximately one
couple
of ceramic caps for every four 5532's to keep them quiet. Then they work
like
a charm. Less noisy than the affordable BiFET amps, especially with the low
impedance external components I chose. And low noise was an issue in that
particular circuit. The main drawback of using the 5532's is a higher supply

current. The board draws 500mA @ +/-15V.

JH.