Sony VFET Amplifier Part 2

Official Court Jester
Joined 2003
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something as this .........
from some reason I can't upload any pic in this moment , so I just put it in my DB folder

upload is working now , file deleted from DB , attached here

desired Iq set as 0V65/Rs , where Rs is value of source resistance in CCS

as drawn , 0V65/0R5 ~1A3
 

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Member
Joined 2002
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I think I have enough for a single-pair output version.

Who's gonna do the PCB? :)

If I attempted this one point-to-point, it would look like a Jim Williams sculpture.

I think I'm in the same situation.

Would it make sense to make separate it into two PCBs? The front-end
probably will make a good preamp as well (like the BA-3). And folks
can play with variations on the follower...

Dennis
 
Member
Joined 2006
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One option is to make a single-ended SIT amplifier using a P channel follower
and biased by a constant current source.

Very easy to do.

I certainly can deliver that and so you guys should consider buying those up.

That said, I would still like to see some of these PP circuits built.

...you will if i have anything to say about it,

I have 8 pairs so if i have any luck i should get 4 sensibly matched ones.


i intend to make this a tribute amp...to your generosity of course and to a time when brilliant minds worked to produce great audio amps....and not just "good enough" as SL put's it.


:cool:
 
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Oh well...

I found this thread yesterday, got all frothed in the mouth and tried to order some pairs, too late.

I ordered some 2SJ28 instead, anticipating a design that might provide some of the magic described in your article. One can only hope!
 
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I had purchased 2 pairs for the CX1 build, and am about to start that one. I am following Michael's Hangout thread, and bought and returned some 2SK182ES parts that were not good. I ordered another 4 pair of the 2SJ28 and 2SK82 for what I was thinking would be a 2SK82 l'amp and the CX2 (assuming 2 pair for CX2 like the CX1 is).

Now I am guessing I need to get MR's frankentracer built, and see if I can match up some of my pairs for the CX2, and use the less matched ones for the CX1.

If matches don't work, I can look at whatever else NP can cook up, he sounds dissappointed that his article came out, just as the VFet source dries up.

Thanks for the CX2 Nelson!
 

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????

Note that not every country can shop with TB, and many TB sellers cannot communicate with English (not sure about this one). I bought some Yamaha 2SK76/SJ26 from this shop before, and as far as I can tell they are authentic.
I have never had any interest on PP design, but this beast seems different. I'm so lucky that i have a colleague worker who is located in china and help me to buy 4pairs (is it enough?), and hopefully they are genuine. I already have 3pairs of 2SK82 from acronman intended for sit l'amp
 

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These people show some in stock
Aliexpress.com : Buy SONY 2SK82 V FET from Reliable fet transistors suppliers on Eternal HONG's store | Alibaba Group

No idea if they're authentic, though. Any gamblers here?

I think these is the company I wrote, asked more pictures (from the actual items :Pinoc:) unfortunately I never get any answer (yet)
Based on the picture they posted look authentic but can be the usually Chinese method (trick) post original pictures and ship counter faith items.
 
I do have two pair for these project but I would be also interested on Mr. Pass Class A project.
That two pair useless for these project.
I post that amp circuit here, in case that will be a problem please feel free to remove it.:)
Thank you
I do not want to hijack the forum! :smash:
Greetings
 

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