KT-88 vs. EL34

bpoletti, you may be right. I had heard however that some, including possibly the above responders, have converted and found the EL34 to sound "better" on the same amplifier so the design wasn't a variable. On the other hand, the outlay of this type of tube amp generally is relatively straightforward. The one important variable that can truly influence the character of a tube amp IMHO is its output transformers because, as an inductor, evenness, peakiness, etc. are most influenced here. It's possible that the different loading that the EL34s place on the primary could account for the differences in sound. What do you think?

6L6GTB sweeter than EL34 - RCA black plates. 

Modjeski designed his RM-9 specifically for use with the EL34 (four per channel for 100w/per in the Mk.1, 125/per in the Mk.2), his RM-200 for the KT88 (two per channel for 100w/per at 8 ohms, more at 4!). But the 200 can also be run with KT-120’s (though not the KT-150---the transformers get too hot at the required plate voltages).

Hey,
Re: Some people say that say KT88s would be "better" than EL34s. Not sure, so subjective, and like the prior note above, also depends on amp design.

E.,g I have a PrimaLuna Dialogue HP Int. Amp, and have started out with EL34s, but even in triode mode, it sounds "dry" not sweet. and even sounds a bit thin in triode and ultra linear mode. so I'm going from EL34s to KT88s for more body, texture, timbre. Case in point, its hard to tell how the sound will be with certain tubes. Unfortunately, we just have to tube roll to find out.

I googled EL34 vs 6L6 and was surprised at how much info there was on such a specific topic, including YouTube videos of guitarists comparing them. Of course the tests were in regard to heavy metal guitar amps and not critical listening but I think I preferred noromance's 6L6 recommendation. Should be fun to try since I have a nostalgic interest in the 6L6 anyway!

My question now is: how different, if any, are the bias voltage settings between the EL34 (which I think I know) and the 6L6 (which I don't know)? Are they truly drop-in replacements? Thanks, Andy