While they last...

@WBS - thanks for your reply, and advice 🙂
ACA are sold out until Q3 of this year.

I bought 6 V-Fets just in case, something goes wrong.

I kind of have a room full of amplifiers that i settled on, but recently have found that for me, it is just best to aim for exactly what would make me happy.
I kind of get excited about the small details, which mounting screws to use, crimping tools, etc.. It is sort of the way i am, which is why i felt so comfortable reading the posts here with so many people obsessed with all the small details also. :hug:

You may still be able to get the PCBs from RudyRatlos (member). They will be slightly different from the store version but very good. All the components are easy to source. The enclosure is available from DIYAudio store, albeit without the marking or drilling but the drillings are easy to do.
 
.....
I wonder if I now will get too many SITs.......if that is possible?.....

no.

...... but "by accident" are nice for audio-use also.

Why did the production of these devices stop?
Because MOSFETs are used now instead (cheaper)?

simple as that - they're good enough for audio and be happy because of fact

regarding production - don't even ask that , no benefits in knowing - simply looking at various reasons from which many production ceased

small JFets - as Pa said many times - Audio is quite small niche of all electronic production, and keeping with expensive production for generally small series once becomes too cumbersome

Semisouth - who would say that parts made for actual Industry - inverters, switching circuits, energetic in general - can vanish ?

LU1014 - same applies

etc.

not to mention (probably true) info that Tokin factory was damaged in quake/Tsunami, maybe even related to Fukushima tragedy ( can't remember details)

so - all sorts of reasons, some related to money side of production, some related to Corporate (I)Logic, some .......
 
It will be interesting to see what a single THF-51 can to in terms of power. Maybe especially power in a 4 ohm load. Probably more powerful than the Sony VFET amp?

But first we need to have part2 of VFET amp "finished" before we will see suggestions for "Papa amps" where "While they last...." is used?

Think I read that these "old" SITs was used in solar energy area for power switching. As this area has not been less important......it seems......maybe we will see some new power devices in the future that is also good for audio......who knows.....
 
Transistor manufacturers recommend mounting screw torque settings of between 0.8Nm and 1.0Nm. Passlabs use 0.9Nm. This has been discussed in another thread a week or so ago. Zen Mod posted some links to manufacturer specs.


I bought this toy, adjusted it to 0.9Nm and realized how badly I’ve been over tightening transistors...

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