Official M2 schematic

do I have the correct values for the resistors labeled here?
 

Attachments

  • psu.jpg
    psu.jpg
    37.8 KB · Views: 623
M2 is singing

Hi All.

with M2 every day is Xmas
There is only to say: it's true!

Big Thanks for all given Tipps by members here, for Teabags quality UMS- Boards.

To use my big heat sinks i have to send first the Aleph J in vacancy 😛.
With all advices careful reading i could lucky set up the M2 with the Toshibas
SJ201; SK1530.
The modification to 0,33 Ohm Degeneration and without 221 Ohm works from
first switch ON in stable 560mV.
With Offset i have tried 3 times, because negativ offset; first change- one site 47k to 53,6k was to much; second change 53,6k to 56k works perfect on
both Channels to zeroing offset.
Time to listen music. 🙂 😛.

After any days, burning in:
So much impressed with clarity, smooth brilliant tonality, wide open image.
The dynamic jumps are impressing me too- there is not all quit flat presented since digitally possibilities.

I only have to rework for better cooling the Transistors- for my opinion 70°C
or more is a bit to hot- seems i'm a bit scary. 😀
Next step is to spend creativity for real nice case.

Now i know why ZM is falling in love for M2.
Yes, only to say Thank you very much Mr. Nelson Pass- awesome Genius!

Because that i understand a bit more the way it comes to DEF- Amp topology.
Begin was any years earlier, i know.
 

Attachments

  • PIC_0402.jpg
    PIC_0402.jpg
    428.4 KB · Views: 596
  • PIC_0408.jpg
    PIC_0408.jpg
    625.4 KB · Views: 572
  • PIC_0406.jpg
    PIC_0406.jpg
    583 KB · Views: 545
  • PIC_0409.jpg
    PIC_0409.jpg
    449.2 KB · Views: 560
With all advices careful reading i could lucky set up the M2 with the Toshibas
SJ201; SK1530.
The modification to 0,33 Ohm Degeneration and without 221 Ohm works from
first switch ON in stable 560mV.
With Offset i have tried 3 times, because negativ offset; first change- one site 47k to 53,6k was to much; second change 53,6k to 56k works perfect on

Hi.
I also built M2 with the Toshibas SJ201 & SK1530 but with the original values of degeneration resistors = 0.47 Ohm and R11 = 221 Ohm (to get zero offset I increased the value of R7 to 51K). PSU voltage under load is +/- 22V, Iq = 1.46A.
I use M2 with 4 Ohm speakers, should I perform the modifications and reduce the degeneration resistors to 0.33 Ohm and R11 to 0 Ohm?
Is it recommended modification or not worth it?
 
Last edited:
STOP PRESS - STOP PRESS

Yesterday the custom ordered Noratel toroidal arrived 240V - 300VA - 2 X 18 fitted with flux shielding ring
Today is Wednesday in Australia. and I wasted no time and fitted it to my M2
Very neat and tidy job if I say so myself

Result - The hum has exited the building
Experiencing - Total bliss as in a noiseless vacuum kind of way -

Now I can truely enjoy the beauty of the M2 and the music I like to listen to
Will post a photo when I tie back the cables ect

I would also like to express my sincere thanks to all the members that helped with this puzzling issue
In the end, the best explanation I can come up with is that the previous toroidal was not a good match for this amp

The new toroidal fixed the hum issue in a snap, So let that be a lesson to you all

FR
 
STOP PRESS - STOP PRESS

Yesterday the custom ordered Noratel toroidal arrived 240V - 300VA - 2 X 18 fitted with flux shielding ring
Today is Wednesday in Australia. and I wasted no time and fitted it to my M2
Very neat and tidy job if I say so myself

Result - The hum has exited the building
Experiencing - Total bliss as in a noiseless vacuum kind of way -

Now I can truely enjoy the beauty of the M2 and the music I like to listen to
Will post a photo when I tie back the cables ect

I would also like to express my sincere thanks to all the members that helped with this puzzling issue
In the end, the best explanation I can come up with is that the previous toroidal was not a good match for this amp

The new toroidal fixed the hum issue in a snap, So let that be a lesson to you all

FR

I am very happy that you found and fixed the problem.