Have you tried a KT88 Wizard? It doesn’t translate exactly the same way you might expect normally with those tubes (which I usually don’t care for). I didn’t actually prefer the highs on the EL34 MTL or MC I had and in either case if aggressive highs were my priority I would choose one of my Herm recs, especially the triple 2ch
The question also was which is heaviest, which is not the same question as which is most aggressive or razor sharp. The extra low end thump and horsepower of a KT88 plus its transformers design around it result in a heavier sound. Some other amps I have are debatably heavier anyway if that’s the main criteria, but it’s I think about as heavy as one can get for a Wizard (maybe more so with the KT200 version). It sounds like heaviness maybe isn’t the number 1 thing you’re looking for with it. We all have our own uses with these amps. For me I like to play most to an amp’s inherent strengths over other amps. For the wizards I feel that is clarity/defitnion, punch and openness and KT88’s and 6550’s will have that over 34’s. I would though get a 50w 34 HR for something different if I can sell enough stuff. I do also love the EL34 growl and uppermids as much as anyone, although wizards don’t IME really get that as well as Marshall’s any even with them
