My Peavy Classic 50 needed new tubes after 15 years of use. After visiting a lot of relevant sites and reading a lot of threads in forums, I decided to go for the long trusted Sovtek EL84. My amp uses 4 of them, so I bought 2 pairs (need to change all 4). I decided to risk and change the tubes myself; the fact is that they were not matched, so they might not work or might need to take them to an expert to check the bias.
Anyway, I was lucky enough not to have any problems. The tubes matched just fine and really transformed the old trusted tweed with the 2 blue marvels. These tubes were meant to offer a robust, well-rounded tone with excellent clarity and definition, especially in the midrange, add warmth and smoothness, enhancing the amp's natural response and providing a tighter low-end with rich harmonics. And so they did! While keeping the character of the amp (great clean sound, really responding to the volume knob of your guitar, great for stacking pedals), the lead channel was truly transformed! In combination with the presence knob, I can reach great sounds usually met in more modern, hi-gain amps. The harmonics are so rich, that even without the use of reverb or other pedals, my guitars sound awesome (Fender Strat Lonestar, Vintage V58 JD, Harley Benton Fusion-T HH Roasted SSP, Ibanez AS73) in every context (blues, rock, heavy). A great choice for the output stage of your amp.
