7 Easy Pieces

[Nelson Pass]

Here we see the same thing as GC-SS-3a, but without the
SuperSymmetry jazz, just a pair of chip amps. The voltage
sources will be low values, as will the output resistors,
and additional output stage is provided by the DC difference
in the output voltages across those output resistors. The
load output sees the split value, so there's no DC seen there.
You also get the advantage of delivering about twice the
current as a single chip amp.

[Nelson Pass]

Does the same thing for a balanced input circuit. Generally
you want the pots at equal value, but for the most perfect
common mode input rejection, separate pots allow trimming.

[Nelson Pass]

You might find this a trivial circuit, but for those who
don't know it, it can be very important. Chip amplifiers
have enormous amounts of open loop gain (120 dB = 1,000,000)
which can create stability problems when the circuit is set
for low gain, say only 10 or 20 dB. This circuit places a
resistor to ground at the negative input, which throws away
some of the open loop gain, resulting in less feedback. In
fact you can put a variable resistor here, and tune the
amount of feedback to taste.

[Nelson Pass]

How can we resist not making a Zen amp with such a current
source? Here we see that the Aleph current source is easily
duplicated by a chip amp.

[Melon Head]

This looks like a really interesting thread are the articles/pdfs in the first post still available

[Zen Mod]

just compare file names with those pics posted last in thread ;

pdf's were same pictures , no text

[Variac]

OK , I did a shocking thing! I added the text to the schematics.
But I need you guys to check it carefully. I don't want Papa to appear to be capable of error!