Recently the bassist in my band got an Aguilar Tone Hammer amp. It's the size and weight of an internet modem. It's my understanding that the way this is possible is because it's "class D", and it uses a special kind of cable from the amp to the cab rather than a normal 1/4". I'm a little jealous. If this kind of shit is possible, then why aren't there guitar amps like this? Or since it's so small and light, why not just build it right into the Kemper or Fractal unit? I once owned a Vox modeling amp that had a button to change the "tone" between "class A" and "class B", and it changed the tone in a marginal way. Though this difference is just a simulation on that Vox, its basis must be in the reality that the power class does has some kind of effect on tone. What is that effect? Is it specific, quantifiable? If I'm being totally honest, I don't really understand what these classes are. Premium tube amps are class A, I know that. I've seen a Laney amp that though it is all tube does allow you to switch between class A and class B (would that give it a volume boost?). These super high wattage amps like the Aguilar are class D. Where is class C? Is it like B batteries? B batteries and class C power weren't rescued from their bunker in Area 51?