Yeah, a good read!

I used to have a p-t-p tube head that was designed to run ANY two tubes easily, and I do mean any from KT's to 6L6 to EL34...well not the small sockets but all else OK. And it had separate master volumes for each tube too, so you could literally not only test EL34 and 6L6 side by side and blend them any way you want.

I gave the amp to my then guitarist...but anyway, I learned I definitely like 34's infinitely better, as I don't ever want a totally clean sound, and I do need the punch...6L's are fine in many amps but that Marshall power tube crunch is where it's at for me. I like 84's the best though because they give that same sound and more versatility and at lower volumes.