Official M2 schematic

Factory original untampered-with, even better.

I totally agree. I just got my M2 up and running using Tea-Bag's boards,Mosfets and Edcors-----big thank you to him :). The sound is great top to bottom with 89db New Large Advents. Lots of bass and sparkling highs. I did not use the jfet buffer, am running it directly from a Schitt Magni 2 (preamp outputs). Lots of drive. Now to spend the rest of the day breaking in and listening to this gem.
I've built an Aleph J and an F6 so I have some reference points.This hobby is really satisfying,build your own and enjoy the fruits of your labour. None of it possible of course without Mr. Pass's generosity and the Diy helpful people ,thank you Nelson and crew.
 
Hi" I am hanging in my inspiration M2 chassis because I has realized the input transformers are very closed each other. Would it be okay if I place them in this location? Interference is a concern.
Thanks you,
 

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On P3

As implied elsewhere, I have added a "P3" to my M2 built. That is, a 200 Ohm 20 turn potentiometer over R3 and R4.

To measure the impact of the pot to the harmonics I used the on-board sound of my PC and a little FFT program, suggested in this forum. Measurements were taken at 1W into a 8Ohm resistor.

The result is: the M2 doesn't seem to care about P3, at least not to the level my simple setup allows to be measured. Irrespective of where I turn P3 (and what voltage I get at the input of the autoformer), I measure -92dB for H2 and -83dB for H3. I can use it to cancel the voltage, but that seems to be it.

With a few plugs I can turn my M2 built to become an F5 (same JFETs and MOSFETs). In the F5 configuration I can conveniently dial H2 in and out (below -100dB) while H3 more or less stays at -92dB.
Interestingly, the setting where H2 vanishes seems to be right in the middle of the pot. I guess this speaks to the expert matching by Spencer.

Maybe you find this interesting.