So... I'm not really up to spec on my knowledge of tube amps. I heard from a friend that you can change the type of tubes out of tube amps to add extra gain and such. Not just brands of tubes ACTUAL tube types themselves he means. Like EL34's to 6L6's (I think they're right?).

Is this true or is he talking out of his arse?

Cheers.. sorry if this is a completely stupid question. I'd just like that extra bit of headroom on my gain atm because its cranked atm. :P
It requires modifying the amp, but it can be done.
I don't give a shit if you listen to me or not
there was a seymour duncan amp they made ages ago you could do that with, but not normal amps, unless you get somehting done to them
It depends on the amp and the type of tubes, etc but you can sometimes go from El34 to 6l6 with only a bias change.

If you just want more headroom, get some lower gain preamp tubes- 12AT7, etc.
but can't you put different members of the same tube family in? I think I remember seeing a page about the different gain characteristics of the 12A_7 family once.
^ As far as preamp tubes go, yes, as long as they're the same family you can use them interchangeably.

Colin, I was under the impression that there was also something slightly different about the pin configuration on EL34s v. 6L6 - not layout, per se, but function.
Hi, I'm Peter
^Nope, same pinout. To switch, usually you just need a rebias, and maybe higher spec screen resistors- that might have been what you were thinking of.