Slajeune's tube buffer revisited: better at 24 volts?

[brad]

I've been thinking about Slajeune's tube clipper/buffer lately, because I reckon it would be a fun DIY project if something useful could come of it.  It had a nice slightly compressed tone to it running on 12 volts, but I was thinking...what if it was run closer to its maxiumum voltage spec at 24 volts?  What effect would the higher voltage have; boost, lower noise?

In an effort to keep things super simple, would it be possible to use a lamp of some description in series with the 12AJ6's heater to half the 24v?  The tube itself has a pretty wide ball-park in terms of what voltages it can operate under since it's designed for car radios ect, so I thought it would be pretty cool if it would be possible to ditch things like voltage regulators and dividers.

Anyhow...anyone have any ideas?  The schematic is here -just remove the clipping diodes and 1M pot for the buffer:
http://www.sopht.ca/schematics/tube-tube_screamer.jpg

[brad]

Ok...here's a quick stab at something using a bias method picked somewhere out of the ether (I swear I've seen it used before!).

Boost?  Buffer?  Not work at all?

[markr04]

You won't hear a difference between 12v and 24v. As you get closer to 200v, there is some difference.

[brad]

I should have mentioned...the 12AJ6 was used in car radios, so it runs at its optimum at low voltages.  Here's the datasheet:

http://www.mif.pg.gda.pl/homepages/frank/sheets/137/1/12AJ6.pdf

I know I post a lot about this particular tube, but I just think it would be great to find a use for it (or other space charge tubes for that matter) in stompboxes.  It's already been established that Slajeune's original circuit works as a buffer of sorts, and sounds pretty darn cool too...so now it's just a matter of exploring the possibilities. 

[markr04]

Hmph... I didn't see that part of your diagram until now. Sounds interesting. Do you know of any low-voltage triodes in the 12ax7/9-pin size?

[RLBJR65]

You could use a 24v transformer with a 12v ct. See the latest version of the Sopht amp.
http://www.sopht.ca/index.php?s=27

Markr04 The 12u7 is a twin triode. http://www.mif.pg.gda.pl/cgi-bin/vs4.pl

Edit: here is also a link to some other space charge tubes http://www.duntemann.com/12vtubes/12vtubesindex.htm

[brad]

What about using a charge pump to bring 12v up to 24?