Help me pick out some tubes

I got into using dirt in my sound from amps which had dirt channels. I believed that distortion had to come from tubes. That's what all the magazines said! Then along my playing journey I got into single channel amps for various reasons, and felt I needed a tube pedal at least for my dirt. My favourite of all of them was/is the Badcat Two-tone, which is a Vox top-boost preamp in a box. It uses two 12ax7s running at full B+ voltage via a transformer built into the box and it runs off wall voltage. There are others which are very good too - the Kingsleys are excellent and work in a similar fashion with different flavours available.

But because the Badcat has the transformer inside the enclosure noise can be an issue. Mine was ok - the Matchless versions are smaller therefore noisier, as the transformer is closer to the very sensitive 12ax7 circuitry. Layout is critical in these things because space is tight and the high voltages make everything susceptible to picking up noise and hum.

Then I discovered that I could get sounds I liked as much or possibly even more with SS pedals. I did a lot of blind testing and was delighted/dismayed to find that often I couldn't tell the difference between a tube OD and a well designed SS OD. It's easy to pick a Tubescreamer as a SS pedal if you use it purely for dirt. But a more natural sounding pedal is not so easy to pick in blind testing - it's surprising.

The benefits to me of my favourite SS ODs are things like size, noise and consistency. I can build my favourites into a 1590B or two of them into a 1590BB. They can be extremely quiet. And I don't have to worry about varying wall voltages or tube wear affecting my signal in audible ways. And, having worked on the Badcat after an outdoor gig blew the power transformer (generators and guitar amps don't mix well) I know that 9V pedals are less likely to zap my fingers! I've never got a buzz from an amp but the tube preamps have serious voltages all over the place. Treat them like an amplifier. It makes swapping tubes tedious because there is potential HV right where you might want to put fingers to ease tubes out of sockets.

This mainly applies to pedals using tubes at proper amp voltages. The pedals can sound fantastic and I still love the Two-tone. But I've found the convenience and affordability of building SS ODs very attractive and the main reason I had for using tubes - sound - is just about moot.

So don't let me put you off! It's a lot of fun using tubes in pedals. And easy to change the sound because tubes all sound different. More and more I turn to JJs because I like the sound, the cost and the consistency. Also I don't like New Sensor as a company and I don't want to buy Russian right now!
 
What kind of tubes can I get to experiment with that don’t require HV? I’ve got plenty of breadboard worthy components and just looking for something new. I would like to try Chuck’s build when I pull the trigger on them
 
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Try higher plate voltage. Better to run the filaments at the correct voltage. Running a 12V filament at 9V can produce unpredictable results.
I've had pretty good luck running 12V filaments at 9V. Anything below 8 starts to get dicey, but 9V has been fine. Lower current draw, less heat, and longer tube life, but agreed you don't want to go too low.
Can charge pumps be used to acheive a reasonable voltage?
Depending on the tube, sure. There's a commercially available preamp out there that uses a charge pump for a B+ of 27V. It's fine. 12AX7 doesn't like low voltage as much so wouldn't sound as good, but something like a 12AU7 runs fine with 27V up there.
 
Can charge pumps be used to acheive a reasonable voltage?
You can add as many stages of diodes/caps as you like practically, but the quantity required for anything over 50V (70 if you go with a 12V supply, which you're gonna want if you're playing with triodes any-who) makes it a bit impractical...

I made this project some time back, layout ain't perfect but it works and is a fun little amp, a 1W(ish) AC30 to fit a 1590BB with self-split triode output stage, MAX1771 SMPS & MOSFET source follower, got the layout still if you desire.

DSC01268_zpsw8arqtsw.jpg
 
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