This thread has some good discussion on the topic of power tubes:
http://www.jemsite.com/forums/showth...2&page=2&pp=15
This is probably one of those "Coke vs. Pepsi" debates... everyone's gonna have their own preference.
I've had over a dozen tube amps over the years, some of which ran on 6L6's (Mesa Recto, Mesa 2:90,
Crate Blue Voodoo), some of which ran on EL34's (Marshall TSL122, Egnater TOL, Carvin Legacy, Carvin TS100, Rivera Knucklehead), some that used both (Mesa Mark IV, Randall RT2/50), then others that ran on EL84's (Mesa Nomad 45, Mesa Subway Rocket, Crate VC50
or 6V6's (
Fender Deluxe Reverb). I've experimented with various stock tubes (Mesa/Sovtek, Fender, Ruby, Groove Tubes) and replacements (SED, EH, JJ's). Because all the amps have different preamp circuits, speaker configurations, etc, they can be difficult to compare, so I'll concentrate on the Mark IV and Randall RT2/50, since they use both types of power tubes with a common preamp and speaker configuration.
Between the two, I tend to prefer the 6L6. 6L6's seem more tonally balanced to me. Notes sound fatter, rounder, perhaps a bit warmer. EL34's seem to offer a little more mid-high frequency boost, which makes them sound colder, thinner, even a little brittle at times. EL34's may be better for crunch, but 6L6's often have the upper hand for clean work. (Again, this is based on my tonal preferences.)
--B
