I'd like to create a current list of amp heads that have clean/dirty channels that are switchable on the fly. That means independent control over not only input gain for both clean and dirty channels, but master gain controls as well so that channel levels can be controlled independently. I've been poking around the marketplace and reading a ton of info on TB to see what's out there, and there doesn't seem to be a huge selection. There are a bunch of amps that have a "drive" control, or similar function, but not all have a way to switch that function in and out on the fly. Nor do most have a way to normalize clean and dirty levels, which would be critical for use in a live situation. I'm mostly interested in small-form-factor amps. The don't have to be micro, per se, but I hauled around a 80lb pre/power rack for almost 20 years and I'm not going back to that. Something less than 20lbs, 500 to 1000 watts, good DI, etc. For the sake of inclusion I'd be open to any heads of a "reasonable" weight (significantly less than 80lbs). I'd like to keep the list to amps currently in production. The list thus far: Gallien Kruger MB500 Gallien Kruger MB800 Gallien Kruger MB Fusion 500 Gallien Kruger MB Fusion 800 Orange OB1-500 Darkglass Microtubes 700 Genzler Magellan 800 Fender Rumble 500 Fender Bassman 500 I feel like I must be missing some models (or a bunch). Please feel free to post up your experience with any of the above models, or a suggestion for another model that has the clean/dirty switchable function.