let me paraphrase what I already wrote ( as answer to same question ) on Baby DiyA :
consider that we have rails of +/-22Vdc
that means (not counting losses precisely) that we have 44Vpp envelope for output swing
amp's gain is 5V/V (autoformer ratio)
so , for full blast on output we need 44Vpp/50= 8.8Vpp at input
that's 8.8/2/1.41= 3.11Vrms
so , if there is any idiot available ( and believe me , it always is ) , he certainly will bang full blast of something into amp's input
in that case , output node (point where diodes are connected ) will try to go both to roof and cellar , resulting in heavy clipping and most probably even more damage
so , just imagine effect of clamping diodes (D1-D2-D3) - they are clamping output node to rails , limiting max . signal amplitude
NB that output node is in strong correlation with mosfet gates , so clamping of outout is in fact achieved with gate clamping
Q6 and Q7 are there to maintain no more than 1V25 across corresponding resistors , saving LED from nasty peaks and maintaining smooth biasing
btw. did you put second schematic , framed , on the wall ?
Thanks ZM ! Now I understand. No just pictures of precious VFETs on the wall 😉
i was deeply impressed by these lines in Tone Audio December 2010 from Jeff Dorgey:
"Removing the $60,000 pair of Burmester 911 mk. 3 monoblocks in my reference system, the M2 held its own, with even slightly more inner detail than the German monster amps. This amplifier was able to take hold of the GamuT S9’s with enough control that a few casual visitors didn’t even know the Burmester amplifiers were no longer in the system!"
"Removing the $60,000 pair of Burmester 911 mk. 3 monoblocks in my reference system, the M2 held its own, with even slightly more inner detail than the German monster amps. This amplifier was able to take hold of the GamuT S9’s with enough control that a few casual visitors didn’t even know the Burmester amplifiers were no longer in the system!"
My German dealer says:
the WSM Series should be the equal to the PC Series a Little bit more wattage.
I want to use the WSM Series but im a Little bit concerned that it will vary to much from the PC Series.
Have someone a little bit experience with this transformers?
And can say somthing about it.
thanks Alex
the WSM Series should be the equal to the PC Series a Little bit more wattage.
I want to use the WSM Series but im a Little bit concerned that it will vary to much from the PC Series.
Have someone a little bit experience with this transformers?
And can say somthing about it.
thanks Alex
My German dealer says:
the WSM Series should be the equal to the PC Series a Little bit more wattage.
I want to use the WSM Series but im a Little bit concerned that it will vary to much from the PC Series.
Have someone a little bit experience with this transformers?
And can say somthing about it.
thanks Alex
They are cheap. Buy both put one of each in separate channels, test which is best.
Job done.
extremely dangerous one (Shark)
edit:
as countermeasure/punishment , I'm going to suspend my constant adoption plea for at least 6 months
![]()
The real punishment is that Papa decided to adopt me instead. Adoption papers are being signed right now.
Hahaha
My German dealer says:
the WSM Series should be the equal to the PC Series a Little bit more wattage.
I want to use the WSM Series but im a Little bit concerned that it will vary to much from the PC Series.
Have someone a little bit experience with this transformers?
And can say somthing about it.
thanks Alex
I think it's one is the right one, choose 600:15k.
https://www.edcorusa.com/pc_series
The German dealer is more expensive and doesn't have all types.
But even ordering in the States you have to wait 6 weeks for production.
I did.....🙂
Look at the price!
My German dealer says:
[...]
thanks Alex
Can you tell me, where I can get those in germany?
Thanks,
Ulf
from me… 🙂
if you don't like me here…
https://www.don-audio.com/Neu-Edcor-transformer-Europa-Vertrieb-1
but they don't have them available….

if you don't like me here…
https://www.don-audio.com/Neu-Edcor-transformer-Europa-Vertrieb-1
but they don't have them available….

Are all the diodes and the LMs a bit necessary because we have no feedback loop?
Or are they luxury?
Or are they luxury?
well , from my explanation and Papa's punch lines ......... I would say that 3 diodes aren't necessary for sane user , but two LM385 are necessary - for better sleep
really functional only in heavy load circumstances ....... but you never know what Cats in house are going to do with speaker cables/terminals/interconnects
if vacuuming the room and cleaning is your job , leave them out too; if Frau is doing at least part of that , put them in
😉
really functional only in heavy load circumstances ....... but you never know what Cats in house are going to do with speaker cables/terminals/interconnects
if vacuuming the room and cleaning is your job , leave them out too; if Frau is doing at least part of that , put them in
😉
….because we never saw this features in F4 or F6 or J2 before I must conclude that
the day Nelson made the M2 circuit somebody new in the house was vacuum cleaning or it was his birthday and he spent some extra features to this amp……
😀
the day Nelson made the M2 circuit somebody new in the house was vacuum cleaning or it was his birthday and he spent some extra features to this amp……
😀
finally i found the shielding i used two years ago for the mains transformer in M2
magnnetic shieldings for toroidal tranformers
magnnetic shieldings for toroidal tranformers
….because we never saw this features in F4 or F6 or J2 before I must conclude that
the day Nelson made the M2 circuit somebody new in the house was vacuum cleaning or it was his birthday and he spent some extra features to this amp……
😀
I think that without feedback linearity under all operating conditions becomes more critical. So I think that could have a lot to do with Nelson showing off. 🙂
i assume autopilot bias because no pot for bias setting
dont know if already asked before
if i want to get slightly lower/higher bias, which resistor should be modified? R11?
sorry for silly question 🙂
dont know if already asked before
if i want to get slightly lower/higher bias, which resistor should be modified? R11?
sorry for silly question 🙂
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