6112 Submini's - What are they good for?

[aziltz]

I've currently got a stash of these 6112s.  I was hoping to use them for a small amp, an overdrive or two, a warm acoustic preamp and possibly a mic preamp.

I've seen them mentioned a few times in Rick's tube circuits, but other than that I don't see them much.  Anyone have any circuits or ideas?

[Zapp Brannigan]

Here's 6112 datasheet:
http://www.cicognani.eu/pdf/SUB%20MINIATURE%20TUBES/6112.pdf
As you see, it has quite high amplification factor (~70), it is the same as 6SL7 has, which is also could be a substitution for 12ax7 in some cases (12ax7 has amp. factor ~100, so take it into account), so you may try to use it in GTO Supercharger, for example, or Engl e530 preamp, but don't exceed recommended voltages toо much or you'll get your tubes dead.
Anyway, you can get amp. factor ~ 90 using 220 kOhm plate resistor and 2,7 KOhm cathode resistor (it's just approximate calculations), voltage on the plate must be ~60% of voltage from plate power supply or something like that (this means, that you need ~ 230v DC before plate resistor, and you'll get ~160 v DC on the plate, although it is close to maximum plate voltage the tube can endure).

[CynicalMan]

Design your own!

www.freewebs.com/valvewizard/

[frequencycentral]

6112 Submini's - What are they good for?

Good for selling to me!

[aziltz]

6112 Submini's - What are they good for?

Good for selling to me!

Perhaps...

I also came across this stuff,

http://townsendtubeworks.com/6112.htm

http://amps.zugster.net/projects/subminiature

[aziltz]

and here's a 6112/5902 Amp.

http://sites.google.com/site/jonandersonmn/5902

[Brymus]

Thats the first sub mini amp I recall having an NFB loop,looks kinda like a scaled champ or EVJ

[CynicalMan]

The datasheet for the 5902 in that amp is pretty impressive. It can handle 1000 G of uniform acceleration, can be used up to 80000 feet of altitude, and can handle 165V on the plate and 50mA of cathode current.  
The 5672 can only handle 90V and 5.5mA respectively.

According to an ebay seller, it can put out 1W. With most other submini amps, I guess an NFB loop would make them too quiet.

[zombiwoof]

One of Seymour Duncan's tube pedals uses that tube, but I can't remember which one.

Al