Srajan has the 1st SIT amp for Une dégustation

[wrenchone]

It would be interesting if you could swap some SIT devices with the guy who heads up Digital Do Main in Japan. Apparently, he's keeping some of the old Tokin SIT product line alive for his amplifiers.

[Nelson Pass]

Don't need to. I have a small stash of those.

[wrenchone]

Interesting. Have you compared curves?

[fireworks]

Can anyone post a link that explains what exactly are the SITs, how they work, etc. and why are they better than regular transistors ?
I saw on the Internet that they are supposed to be 1000 times faster than an ordinary transistors ? SAY WHAT ?

[Zen Mod]

naah

they're nothing special
just sand triodes

[Nelson Pass]

Originally Posted by fireworks

Can anyone post a link that explains what exactly are the SITs, how they work, etc. and why are they better than regular transistors ?
I saw on the Internet that they are supposed to be 1000 times faster than an ordinary transistors ? SAY WHAT ?

They are quite fast, but that is not the relevant item. They behave like
tube Triodes, but can do so at voltages and currents of interest to
loudspeakers, removing the need for transformers, heaters, and so on.

I am writing a nice little article on the subject which will make an
appearance after a bit.

[Tea-Bag]

In the meantime, I scoffed up a few of the acroman's stash.

[fireworks]

This is the link where it says that they are 1000 times faster than transistors:

New Scientist - Google Books

However that article is from the 80s so the regular transistors have progressed a lot since then.

The only useful link I found that explains how they work is this:

Junction field-effect transistors : SOLID-STATE DEVICE THEORY

It appears that they are JFETs with the gate inside the channel as opposed to next to it.

Any more info available ?

[VladimirK]

Speaking about a use of SITs, I would remind, that the working point they are usually implemented at is chracterized by relatively low Drain-Source resistance. What this can be useful for?
As in a case with NFB and THD, it is better to insure maximum linearity before the closing of NFB loop.
Same is true with the output impedance Zout. Usually it is lowered by the action of NFB. But, again, much better to insure quite low Zout, before the closing the NFB loop, and this could be done just due to triode-like output characteristics of SITs.

[rsdio]

Originally Posted by Nelson Pass

They behave like tube Triodes, but can do so at voltages and currents of interest to loudspeakers, removing the need for transformers, heaters, and so on.

Forgive me for asking a potentially obvious question, but I assume that tube amplifiers generally operate in the range of hundreds of volts (300 V, 700 V) where loudspeakers are happier with tens of volts (25 V, 50 V max supply). What currents are interesting for loudspeakers? (excepting the exotics like planars, electrostatics - or include them if you'd like to be comprehensive)

P.S. Looking forward to the article!