Official M2 schematic

Official Court Jester
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just re-read my post with exact resistors nomenclature :

ref. to schm in post #1 - decrease R13,R14

decrease R11 to (almost) zero

Iq will go up somewhat , but you ought to have that much reserve in heatsinks

so - R13,R14 to 0R33

R11 to zero ; ignore previous post where I typed 100R , referencing R11 original value - that was brainfart or typo , whatever
 
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Good news RussellC. Yes tell us first impressions compared to your recent F6 build.

I am finding it all around more enjoyable than F-6 right now, will have to switch back after more listening. If anything, while M-2 has lots of detail, room echo from venue, micro sounds from acoustic instruments, etc., I find the F-6 maybe MORE detailed in some ways, approaching ever so slightly over detailed in comparison to M-2. M-2 seems ever so slightly rounded off, but in no way overly so. Plenty of detail. Majestic comes to mind...warm, relaxing very nice amp.

More listening needed, then swap back to F-6. Complementary output stage BA-3 amp still very pleasing as well.

As many have said before, the Pass Firstwatt amps are all good amps, excellent amps, just different good amps!

Russellc
 
Official Court Jester
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I know some of Greeddy Boyz are grasping M2 biasing mechanismus .

those who aren't sure how 's that actually working , better to stay away from tweaks

trimpot is there just for offset , bias is sort of auto ........ tightly determined with source resistors and few resistors connected to optocoupler
 
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I know some of Greeddy Boyz are grasping M2 biasing mechanismus .

those who aren't sure how 's that actually working , better to stay away from tweaks

trimpot is there just for offset , bias is sort of auto ........ tightly determined with source resistors and few resistors connected to optocoupler

On the other hand, one learns more from screwups than things done right..........can get kind of expensive though! ;)
 
I am finding it all around more enjoyable than F-6 right now, will have to switch back after more listening. If anything, while M-2 has lots of detail, room echo from venue, micro sounds from acoustic instruments, etc., I find the F-6 maybe MORE detailed in some ways, approaching ever so slightly over detailed in comparison to M-2. M-2 seems ever so slightly rounded off, but in no way overly so. Plenty of detail. Majestic comes to mind...warm, relaxing very nice amp.



Russellc

You and I pretty much have the same impressions. The F6 is the most revealing amp I have ever heard. Everything in the audio chain better be as good as it or else you will think it is the amp. The F6 is a fantastic amp and was my favorite over the other 2 FW's I have built but this M2 is now my favorite. I compared the M2 with my favorite SET this morning. Both are very good but totally different. The M2 is better high and low and a great sounding smooth mid-range too. The SET is delightfully smooth in the mids with a great all around sound as well. It comes down to personal taste and what one likes at the time and mood they are in and to which I want to listen to at the time. Equally good but different is the way I am going to describe the 2 right now. Rockers will definitely prefer the SS sound. Being my latest build I went straight back to listening to the M2 after doing a short comparison. I am one happy camper.

:D
 
Official Court Jester
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Is it a good idea to use Black Gates for c2 and c3?

E.g.
c2 = BG N 10uf 50v
c3 = BG Std 3300uf 16v

What are minimal requirements for c2 voltage?

Thanks.


for my (old ) ears - there is no difference between :

1.industrial (125 deg. C) Elna electrolytic bypassed with 100nF MKC
2.Elna Silmic bypassed with 100nF MKC
3.Black Gate bypassed with 100nF MKC

except that BG is demanding painstaking long burn in
 
Thank you!

But what are minimal requirements for c2 voltage?

Because of the V requirement of the amps itself 25V would be the minimum, I like 35V to have an extra measure of safety.

I doubt that there is 22 V at C2 but I would have to measure to check, other electronic wizards can do the math and tell you more precisely.
 
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