As regards my Crate amp, I substituted one JAN 12au7 for one of the Russian
(groove tubes) 12ax7 in my 15 watt amp. What a difference!!! Whereas before
I couldn't turn the gain up beyond one or two without a lot of nasty types
of distortion, I'm now able to open it up and fully use my gain to get the
types of sounds I desire. The "clean sound" is now open and clear, and
with the gain upped, I get a full round distortion. Thanks for all your
advise... Ted Kaplan