I have a Peavey Classic 30 with El-84's in the power section. I replaced the preamps, which were chinese crap, with some NOS JAN Phillips 12ax7wa's, and those things made a huge difference in tone, so I'm sure changing the power tubes will make even more of a change. The question is, which brand? Please respond if anybody has a had a good experience with a quality El84 tube other than what was in their amp when they bought it.

I replaced my preamp tubes and got some Svetlanas 6L6GC from the Tube Store. You can get some good advice and good service there. Here’s a link for your tubes.
http://thetubestore.com/el34review.html

I already checked that site- that review is for El-34's, the El-84's big poppa. By the way 6l6Gc's are in the power section, so I hope you didn't stick those in a 12ax7 slot (probably wouldn't fit anyways). Anyways, I'd heard EI's are good tubes, so I bought a quartet of EI El-84's from Triode electronics (best tube deals- www.triodeel.com)We'll see how they do.

I have 4 amps that use EL-84's and I've used probably every import available and I would have to say that the biggest difference happens when I get the amps re-biased ... when they get re-tubed .

I’m sorry soundelixir, but I misread the 84 for 34. (I shouldn’t post at 1:30 AM ).
I replaced my preamp tubes with Tesla/JJ 12AX7A, and also got some Svetlanas 6L6GC, which I’ll put to use in a couple of months, in the power section
I know you’ve gotten your tubes, but here’s the corrected link anyway. http://store.yahoo.com/thetubestore/el846bq5types.html

klasaine- I'm planning on re-biasing my amp, a peavey Classic 30, but I haven't opened it up yet....Do you know if it's got a potentiometer like the marshall's? And also, what is the bias range for an El-84, so I'll know what to reset the bias to?

Soundelixer, I don't re-bias my amps myself,I let a tech do it.I don't have the equiptment or the ability, Sorry.

I called peavey and they said that the Classic 30 was a fixed bias, no need to re-bias. I was curious about this because the Vox's are fixed bias, and I believe the classic 30 is modeled after an AC30; both class A, 4 EL-84 amps. Thanks a lot guys!

Another great place for tubes, in my opinion, is:
http://users.erols.com/bluestat/index.htm#Black

They have a broader selection than The Tube Store, including hard to find Mullards.

Where can I find a Bias King or an Allessandro Bias and Matching Meter?
Thanks.

well, I got some Ei el-84's and jan/phillips 12ax7's in my classic 30. pretty signifigant difference in tone. lot fatter clean tone, and a hell of a lot better distortion; more uniform, not nearly as buzzy, lot creamier and "natural." Great purchase!

Groove Tubes' EL84s are superb. At last check they had two versions: a warmer sounding EL84 and a version that distorts more easily. I use both in my 1967 Deluxe Reverb (with yellowjackets), and they sound great.

Groove tubes just takes chinese and russian tubes and slap their name on it. I've tried them and I prefer NOS american wattage or svetlanas.

I currently have Groove Tubes EL84S tubes in my amp and I'm not nuts about them. Supposed to have more clean headroom than their usual EL84 tubes. Kind of buzzy and fizzy when the amp's really cranked and a serious lack of warmth. Stiff I'd call them. Before the Groove Tubes I had some old RCA's in there that were heavenly. I just got some Ei's off eBay so we'll see how those sound. I'll let you know.

The Ei EL84's sound great in my Tophat King Royale. They are the closest to the old Mullards altho they won't last as long.
The Tesla EL84 is also nice. NOS Philips 6BQ5's are still around. A harder sounding tube with better headroom, but you might like them too.

*Everybody* prefers NOS. The problem is that they're not worth the price--not to me, anyway. I have lots of NOS EL84s, which I use only occasionally (I'm trying to make them last, especially the old GEs and RCAs). They do sound better than new EL84s, but not drastically. I'll admit that the Groove Tubes EL84S is a bit hi-fi sounding in some amps, and the other, lower-headroom version they sell is not for everyone, but at least with Groove Tubes you know what to expect every time you buy them.