SIT Nemesis

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too much parts :D

Haha :D First Némésis was inspired by Western Electric 25B amplifier

https://www.westernelectric.com/static/library/specifications/amplifiers/25b-amplifier.pdf

Can You show us Tokin version photos how minimal number components inside is ? Thanks in advance
Some of this 1920 WE amps work despite a century age is incredible.
Big SIT transistors can do longer time ;)

Western Electric 7A

https://www.westernelectric.com/static/library/specifications/amplifiers/7.pdf

Western Electric 7 A part 8

Westrrn Electric 7A part2
 
nothing very different than the papa sitnemesis, parts are
one pair of input cap grid choke instead of transformer input ( matter of taste)
a pair of Thf51S instead of the semisouth VFET
a pair of TANGO output transformer
a pair of TL431 bias power supply
a pair of CLC 100K 10MH 100K for the power supply
and that's it..

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@ Jan.Didden

Yes we can rather name this "amplification stage with autoformer output".

In "L'Audiophile" nr 41 edition from 1987 was Némésis show compared old (ancien) generic output transformer
performance with updated Tango FG50S version , a much better one :)
Mr. Hiraga says without feedback this amp is excellent for mid-highs in bi-amplified systems.

He use metaphores about audio and amplifiers
" Distiled water is chemicaly pure but many peoples appreciate natural water directly from the source "
" Contemporary producers make them with complex circuits, small size, little weight and cold
but some peoples find music is more beautyful from minimalistic circuits, bigger hardware, heavy and who run hot "
 

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I finished the amp with very simple circuit. The signal path through only two parts (the vfet 2SK180 and the OPT Tango FG-50S).
The self bias with the big 1 Ohm resistor connect to the source pin and the small 47K resistor connect to the gate in to ground. So, my amp circuit have only 4 parts: 1 vfet, 2 resistors and 1 OPT.
There is only one single main power supply (LCLC filter - without regulation), the amp running with Vds = 25Vdc / Id = 2.9A.
The OPT connected 1:1 ratio
I tried to use the red copper and Arctic silver 5 thermal grease so the temp on the vfet only 42 degrees after 80 minutes warm up.
Some images and hope all of you love it....
Thanks!:rolleyes:
P/S: I will match this amp with my ATC SCM7 V3 loudspeakers and make some review later...

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