Specifically, I never did understand the 100W Marshall JCM800 head too well actually...I get it well with clean amps like Twins and I also had a 120W all tube Ampeg at some point, and the JCM900 100W also behaved quite OK, but that 100W 800 series was just insanely loud when it properly opened, it really ripped at the ears even with some protection on, because it just has such a cutting midrange.