Are there enough SIT-1 transistors left to an official DIY amp on this forum?
The mono block version with the adjustment on front would be the most fun to build.
The mono block version with the adjustment on front would be the most fun to build.
There are plenty of SIT transistors available that you can use.
Tokin 2SK182ES / THF-51 from eBay Japan seller
LU1014D from Jims Audio on eBay
KP926B from Russian seller on eBay
I have purchased some of all of these and confirmed with a curve tracer that they are genuine SIT.
Zen Mod and MR have posted SIT DIY designs that you can build today.
If sales of FW SIT-1 pairs declines…...then who knows…..maybe some Pass branded SIT-1's are left for us poor DIY'ers 🙂
There has been some roumors about a new DIY Pass designed amp using exotic transistors.....so I will wait for that and see what it is.
The population of SIT-1 transistors were initially sorted by Vgs, with the
-3V to -4 volt being the most suitable for common-source operation
(SIT 1 and SIT 2 amplifiers) and the -5 to -6V being suitable for common-
drain operation in the SIT 3.
Now we have the remaining -7 and -8 volt parts, and I will be looking
to develop a circuit optimized around those. The quantities are limited
such that I don't think they will be produced by FW, but we'll see what
topology turns up that gets the performance.
-3V to -4 volt being the most suitable for common-source operation
(SIT 1 and SIT 2 amplifiers) and the -5 to -6V being suitable for common-
drain operation in the SIT 3.
Now we have the remaining -7 and -8 volt parts, and I will be looking
to develop a circuit optimized around those. The quantities are limited
such that I don't think they will be produced by FW, but we'll see what
topology turns up that gets the performance.
I do give this guy points for the name. "Fatt Wirst" sounds like something I'd enjoy eating at a ball game, along with a $12 beer.
It just shows how polite and mature you all are...
I thought Fatt Wirst was a claim about the cloner's personal sausage.
Clearly a bit of a dick.
I thought Fatt Wirst was a claim about the cloner's personal sausage.
Clearly a bit of a dick.
Fatt Wirst Tokin appears to be very simple arrangement? Wasn't SIT3 a kind of push pull with carefully matched SIT and MOSFET?
This looks to be single ended Tokin with control MOSFET?
This looks to be single ended Tokin with control MOSFET?
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Hmm, yes, Fatt Wirst Tokin must be a true DEFISIT type. I thought the 2SK182E was a higher power part than the SemiSouth device but I guess it is not.