MEMDIST POWER AMP + JC + TMC - help to set up

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Hi,
I was hot after reading about headamp from peufeu Memory Distortion Philosophies - Part 8 : More tests
and wanted to build higher power version for LS driving.
Please look at the schematic,
I added JC-like coupling within the mirror and VAS
then I wanted use TMC like gnfb correction like Edmond Stuart proposed http://www.diyaudio.com/forums/solid-state/94676-bob-cordell-interview-negative-feedback-336.html
and got this.
Please help to adjust the values/other parameters to obtain the amp possible for working,
I believe that the combination of memdist/TMC correction might give something better that "Lavardin" sound.

Additional explain: I hate global nfb :t_ache: and believe that that solution in most cases spoils the sound,
however
with you help
will this be good sounding?:hug:
 

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Hi
after some time I designed something like this.
As input fet I am going to use BF245B but did not have the models.
The design seems to be a bit from the oscillations
please suggest how to make it more stable.
 

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rewarming memdist power

Hi
after some play with LTSpice I found that this time it is working.
Close to full power has very low thd and nice descending harmonics distribution @~110mA idle.
The circuit has the potential, maybe I will build it someday:rolleyes: = needs 2SK170 or other 50V DC device instead of BF245B which is only up to 30V (only for simulations).
TMC nice lowered the thd.
asc file attached for play & fun:wave:
 

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Last edited:
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