Revisiting some "old" ideas from 1970's - IPS, OPS

See the parts and the values for the normal (left) and normal (right) feedback options.
 

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Try them both and see what you think. I'm interested to hear other's opinion on the nested feedback. Some testing numbers would be good for each option too!
Ok i will mount two 1p2 to this channel and leave the other channel empty according to second option for a try.
For d.c input blocker capacitor i have these, what is preferable to your opinion?
Unfortunately the 10uf don't feet well.
I want to go step by step so this IPS will be tested alone without OUT mounted.
Never i have done this in the past,but now using SMD this is necessary.😉
 

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Ok i will mount two 1p2 to this channel and leave the other channel empty according to second option for a try.
For d.c input blocker capacitor i have these, what is preferable to your opinion?
Unfortunately the 10uf don't feet well.
I want to go step by step so this IPS will be tested alone without OUT mounted.
Never i have done this in the past,but now using SMD this is necessary.😉

Any one of those should work. The bass might roll off a little early with 2.2uF though.

I made up a jumper to plug into the bottom of my board with 100R resistors from PD+ and ND- to NFB for testing. It works well.
 
Any one of those should work. The bass might roll off a little early with 2.2uF though.

I made up a jumper to plug into the bottom of my board with 100R resistors from PD+ and ND- to NFB for testing. It works well.

Right. Just don't forget - in the 1-st case R15 = 27K, in the 2-nd case R15 = 47K.
Good tryk! I will do the same .
Yes Valery i don't forget this(i hope so):nownow:
 
ZERO DISTORTION OUT

Some progress to power amplifier.
An easy to build power stage,clear, beautiful,i wish to play nice too!
This Monster will be alive soon😱
 

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Looking around for the adjustment procedure (R31,R43).
Where i can find this adjustment procedure?

If you go to Index at the 1-st page and click "NS-OPS", you end up here:
Building instructions

Just note - clockwise / counter-clockwise directions are mentioned there, based on the trimmers orientation at my 1-st prototype version.

Anyway, set the bias spreader to the maximum R position, the clamping spreader trimmer - close to the middle R.

First - you set the bias with no signal. Then - set the clamping with signal.