What I'm wondering is how much of a difference there is between power tube brands on a high-gain amp like mine that gets the majority of its overdrive from the preamp section.

I'm in the process of changing out all of my preamp tubes to JJs, and I might do the power tubes with some JJ 6L6's. But if it's not going to make a huge difference in tone I might as well just wait until the stock ones go bad.

My thinking is that I'm not really going for (or getting) any power tube breakup in my amp, so why would the power tubes factor into the tone a whole lot?

Please correct me if this is a misconception -- I want to learn!

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Even without breakup they still impact the tone.

I would get an extra set just to have, if not for any other reason. You never know when a tube will shit out. Why wait a few days without your amp?
This is a contentious topic, but in my experience you're right, it won't matter much. The difference between two tubes of the same type made by different companies are so subtle as to be unnoticeable nine times in ten. The difference between two types of tube probably won't be very noticeable until you start driving them, though that isn't always true--switching from 6L6s to EL34s made my Peavey Triple XXX sound much warmer, for example.

Like I said, this is a point of hot debate. Some people insist that changing from Sovteks to JJs will radically change the whole voice of your amp, others claim there's no tonal difference between EL34s and 6550s. I can only speak from my own experience, and that experience says you should keep using your tubes until they need replacing, then pick the replacements based on price and lifetime. Unless you can afford to keep buying tubes just to try them out, in which case go for it and know that I seethe with jealousy.
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Quote by AcousticMirror
just got for a pair that don't suck.

jj's, eh are fine.

This. You really can't go wrong with JJs. They sound great for modern applications like high gain amps. For vintage tones I'd go for Sovteks.
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Pulling the Sovtek 6L6's out of my Abbey and replacing them with British Brimars made a massive, massive difference. It was noticeably better on all channels. That amp has three channels, the first channel is a non-MV, second a normal MV and the third is high gain.
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Last edited by Cathbard at Jan 31, 2012,