I’ve had one of these for sometime and have used it on and off in my setup, and just started recently to work with it again. its quite amazing sounding and very powerful (for my unit the unity level is between 9-10 o’clock on the master volume!) I bought mine used and though it didn’t have the original 12AX7WB tubes, it sounded quite good to my ears with the 12AX7 Groove Tubes (Russian?) it came with… at some point i decided to try some different 12AX7 tubes and decided to go with Tung-Sol 12AX7 based on this review: http://thetubestore.com/12ax7review.html

I guess was trying to obtain a tube suited for higher gain which is what the pedal is best suited with? but still have good microphonics and relatively low noise (which is not easy for this pedal but not really an issue for me). Now i might be trying to obtain abit more “tame” sound as I am also using this in front of a silicone fuzz face clone to also help as a boost for it, and with both pedals engaged it can sound abit too much (but still awesome as i do like that…).

Just wondering if anyone else has had any experience with using different types of 12AX7 tubes in this pedal and their thoughts?

thanks!