I know this is an ancient thread (well, two years old, anyway), but in the event there's still some interest...

I've played with just this tube in this application (a 12-volt "plate-starved" configuration), and found that in order to make it work, it was necessary to positively-bias the grid. I used a high-resistance voltage divider (2.2m/470k) off the 12-volt supply. This is because the very low plate potential just doesn't provide any plate current on its own.

Once I did that (for both stages, with somewhat different resistor values), it started working quite well. The trick for me was to play with the grid voltage until the plate voltage was around 6 volts (on a 10-meg input impedance voltmeter), roughly in the middle of its linear range.

The 6111 sounds quite nice, but its gain is rather low, so I ended up using an op-amp preamp stage to get enough drive for a good tube crunchy sound.
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Mark Moulding

 

there are so many variations you can do since its low voltage. you won't have to worry about it catching on fire. you can tweak it to your own ears. the original design has DC on the gain pot and no bias on the 2nd stage which isn't a good idea. but it does have a raw tube sound. if you want DC off the gain pot and biasing you can build the Valvemaster