Sony VFET Amplifier Part 2

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Joined 2012
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There are also other options. The Tokin THF-51S is still available. It can be used in a L'Amp single ended amplifier (similar to SIT-1 and SIT-2) or in Zen Mod's Sissy Sit push-pull (similar to SIT-3).

Also there will be Nelson's future DIYAudio offerings.

The Tokin 2SK182ES is also still available and may possibly be of use in some circuits.
 
making your own BOM from schematic is way of learning , even if one need to ask many silly questions

with right cause and outcome , even silly questions are clever

so , don't share your BOMs ..... let them live

:clown:

+1

This was similar advice I was given. I used 1k pots for P3/P4 since I used the Fairchild MOSFETs, and an Antek AS-4225 toroidal power transformer. I built up the BOM and built the amp following Nelson Pass’ schematic and never looked back. As ZM said, you will learn more going this route, and this experience will take you farther in your next projects.

I should add that 6L6’s build guide provided a great visual outline to follow in building this amp properly in stages for testing purposes.
 
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Joined 2002
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If you end up using the 1k single turn pots for P3/P4, note that I had some different resistance measurements than what are listed in Mr. Pass' document for the Sony VFET amplifier:

https://www.diyaudio.com/forums/pass-labs/302380-sony-vfet-illustrated-build-guide-67.html#post5605492

Rich,

Thanks for the link. I plan on following in your footsteps and those of the illustrated build guide in the near future with one small deviation. Once again, it's sounds like you just have to breathe on the one turn pots and things change. To that end I was considering the 25 turn pots, 3296P502LF-ND (5K) for P1 and P2. 3296P102LF-ND (1K) for P3 and P4.

Regards,
Dan
 
VFET2 up and running

I dis get my VFET2 running :D:D:D

First new output board (thanks Teabag) - that got me to the point I could adjustP3 and P4 and actually see changes. Stability was a problem.

Replaced the2SJ28 pair and the 9240. That did it - Set it up at 1.5A and 10mV offset. Now I have the sound I remember. The only downside is I used my last matched pair of 28s. :eek:

Thanks ZM, Dennis and others who provided tips and of course, Nelson for the design.

Best

Bob