Antoinel
I have enjoyed reading about your DEF experiments
Your contributions are both enjoyable and clear.
I have some R085s and will be waiting for Nelson to post the teaser he mentioned - transformer front end with R085s/IRFxxx
Best and thanks
Bob
Hello, Bob. Thank you for your post and kind words. I enjoyed experimenting with DEF and writing about its working. I am still learning. I look forward to the DEF teaser by Mr. Pass and articles about it.
Best regards,
Anton
Hello, Mr. Pass. You bring great news for progress on DEF. May consider the following:
1. A registered trademark for DEF. It is truly unique.
2. One more copy using overall negative feedback.
I look forward to your DEF article.
Article and kit ?
Greedy Boy are interested that fantastic news.
Thanks a bunch Mr. Pass.
Kindest regards
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Most excellent. I have played with the 1208K's also, and they are fine parts,
but a caution is in order - More typical Vgs for my samples is about 7 volts,
which will make it a difficult match for most P channel Mosfets. You may need
a decent population of parts to get the value range you want.
You have already shown in a previous post that Mosfet [pentode-like] and VFET [triode-like] cooperate nicely in a DEF amp to make a very pleasant sounding amplifier. It follows that UJN1208K [pentode-like] which has typical Vgs ~-7V can substitute for 2SK82 of ~similar Vgs. Thus, UJN1208K and 2SJ28 [Vgs ~+7V or higher] become a pseudo complementary push-pull pair in a power amp which uses or does not use overall negative feedback as in the SONY VFET diy amps.
This pair of FETs is not DEF but is an outcome of DEF's broader and unexpected utility.
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Do Mr. Pass write DEF schematic version style with the vfet's too please ?
Many hobby amateurs get alone triode semis in his drawers
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Hmmm your F6 is doing same with My Tannoys.. Very pleasing indeed.
Even better.. is too much to hope for ?
Clearly I would be interested in a 'Kit' when / if you decide
Just returned from travel and checked - yes I have 4 SJDP120R085s - pairs E17A and E23F (Mike's designation)
Yes like Antoinel write is 20 watts with 8 Ohm load but DEF amp can do twice of power
~ 40 watts simply connect efficient speakers with lower 4 Ohm impedance.
IXYS enhacement Mosfet's with SIT's one fantasy about DEF stage
Hello Soundhappy. The voltage output of the preamp which is needed to drive the basic Pass DEF is 36 Vp-p get 20W/8 Ohm. Define the fantasy higher power output of this brute DEF [buffer] and backcalulate its required input signal. May calculate a 70 Vp-p for a preamp output!