So, to my understanding, we can expect 10 W amplifier with no feedback. Frontend will be buffer + transformer. Output semiconductors will be paired as one SIT + one MOSFET, where MOSFET part will act as CCS.
It's more complicated than that.

It's more complicated than that.
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Ah yess. We expect nothing less. Thank you for "raising steam". Hope my kettle will hold the pressure 😀
Not sure if this has come up before, but if I wished to swap out the 47uF & 220uF electrolytics for film caps, what would be the minimum values needed in order to avoid bad things from happening ?
I am curious because several people have done this with the B1 Korgs 10uF ecaps, using 0.22,1, and 3.3uF film subs, reporting a positive improvement.
TIA
I am curious because several people have done this with the B1 Korgs 10uF ecaps, using 0.22,1, and 3.3uF film subs, reporting a positive improvement.
TIA
C1 to C4 are pretty much simply filter caps on the outputs of the TL431 regs. There's nothing to gain from using boutique caps for C1 to C4.
In regard to C5 and C6, the consensus seems to be that they're DC-level shifting caps and are not to be viewed as coupling caps in a strict sense. They more or less correspond to C1 and C2 of the First Watt F4.
Searching the F4 thread, I've gathered the information that the absolute value is not really critical, and that anything above 100uF should do fine. Going lower supposedly results in turn on thumps of the amplifier, and still going lower will form a highpass for the audio signal.
It's been said that it's not worthwhile replacing C5 and C6 in the VFET amp with non-polar, possibly film-foil capacitors.
In regard to C5 and C6, the consensus seems to be that they're DC-level shifting caps and are not to be viewed as coupling caps in a strict sense. They more or less correspond to C1 and C2 of the First Watt F4.
Searching the F4 thread, I've gathered the information that the absolute value is not really critical, and that anything above 100uF should do fine. Going lower supposedly results in turn on thumps of the amplifier, and still going lower will form a highpass for the audio signal.
It's been said that it's not worthwhile replacing C5 and C6 in the VFET amp with non-polar, possibly film-foil capacitors.
Do not Vfet TO-3 are available at Mouser , Digikey etc. or all are NOS ( rare ) transistors for this new kit ?It's more complicated than that.
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Awhile back in the 'What To Do With Those 2SJ28's' thread you mentioned a potential balanced design using 2 VFETs per channel:
I'm curious if a balanced option will be possible with the upcoming 1 VFET kit, for those who have VFETs on hand, or if that was an entirely different design (happy to wait for the unveiling if this reveals too much 😉).
One thing you might want to try is bridging two of these, one with the 2SJ
and the other with the 2SK.
The kit I have in mind has 1 VFET and 3 Mosfets, all in TO-3 packages.
The other option is 2 VFETs and 2 Mosfets for either balanced or stereo,
but getting twice as many VFETs for it remains an issue.
I'm curious if a balanced option will be possible with the upcoming 1 VFET kit, for those who have VFETs on hand, or if that was an entirely different design (happy to wait for the unveiling if this reveals too much 😉).
I have a nice inventory of TO-3 power fets
🙂
That's super cool. My guess is vintage silicon(s) ?
Eventualy this TO-3's have some modern equivalents or substitutes ?
Vfet Part 3 is the most enigmatic one haha
I hear this is gonna be the project for Saturday at Burning Amp. Awesome!!
Information source please ? From BAF team or..?
Attachments
Information source please ? From BAF team or..?
haha, you caught me. I was just stirring the pot. 😉
I hear this is gonna be the project for Saturday at Burning Amp. Awesome!!
Sorry, it is not.
After viewing Burning Amp on YouTube which outlined DEF amplifiers and also the SIT variants I have come here to purchase something which I can build. I would like to ask for direction with 'where to go in order that I might buy these parts/kit/PCB/etc'. Thanks and kind regards, HK
Hi HK,
Your best bet might be the SissySIT:
SissySIT
https://www.diyaudio.com/forums/swa...a-m2-xa25-bstrd-kit-packages.html#post5499526
Babelfish M25, SissySIT - general building tips and tricks
The Tokin SIT should still be available from a couple of sellers and the
PCB and rest of the parts from the Mighty Zen Mod.
Cheers,
Dennis
Your best bet might be the SissySIT:
SissySIT
https://www.diyaudio.com/forums/swa...a-m2-xa25-bstrd-kit-packages.html#post5499526
Babelfish M25, SissySIT - general building tips and tricks
The Tokin SIT should still be available from a couple of sellers and the
PCB and rest of the parts from the Mighty Zen Mod.
Cheers,
Dennis
Sorry for double post, too late to edit.
Can anyone suggest a reliable source for the SIT's, 4pcs?
Thanks, HK./
Can anyone suggest a reliable source for the SIT's, 4pcs?
Thanks, HK./
diyAudio members have purchased genuine SITs from diyAudio member pras1170:
Sell thf-51s 2SK182ES NEW NOS to-79 SIT v-fet, from Japan TOKIN
Sell thf-51s 2SK182ES NEW NOS to-79 SIT v-fet, from Japan TOKIN
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