So I have an Epi Valve Junior head, and I love it. Stock tube compliment is an EXH 12ax7 and a Sovtek EL84.

But out of curiosity, what power tubes could I swap in (WITHOUT having to wire in a new socket) for different response and tone, and what differance would there be? Any help would be lovely.
JJ/Tesla EL84. really responsive, and a bit chimier than the sovteks.

my blues jr had sovtek el84s. i swapped them with JJ/Tesla EL84s, and got those results. i like it.
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I put some vintage tubes in mine that I found at a radio show. A Mullard EL84 and an RCA 12AX7. It was a tremendous upgrade. Totally smoothed the amp out.

The Ei EL84's interest me, too, but I haven't tried them. Only read some intriguing reviews. Tung-sol gets the nod as a great 12AX7.
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Quote by jj1565
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They'll fit, but unless you want to blow your transformer or pay more than the amp's worth to mod it to take a different tube, stick with El84s.
Well anything other than an EL84 won't fit. I went with a Mullard 12AT7 and JJ EL84. Made it chimier but less harsh too. I'd recommend NOS valves if you can get them - muh better and because the amp only has two overall it won't kill your pocket. Sovteks rattled in mine and have this harsh overtone - the new valves crunch more nicely, don't rattle and are smooth but crunchier.
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