I think it depends on the build quality of the preamp more than the tubes. I have had a preamp that used only the 6SN7 family of tubes vs the other that used the 6922 family of tubes. The second pre with the 6922's sounded better because it was a better preamp. I never had a preamp, don't know if one is even available, that would accept both 6SN7 or 6922's which would be a better way to compare them, at least for that particular preamp. I see many posts from people that hate the 6H30 super tubes and others swear by them. It all boils down to the sound that is most pleasing to your ears!
