4 tube preamp channels, 150W of power, and 2 separate 16 digital effects sections! The channels are clean, overdrive 1, overdrive 2, and an acoustic simulator channel (makes any electric sound like an acoustic). Because all 4 channels are footswitchable (switch included), this amp gives guitarists ample flexibility onstage. 2 digital effects sections enhance this flexibility. One section is dedicated to the clean and simulator channels, the other to the overdrive channels. All effects are tweakable via mix, adjust, and select knobs, and are on/off footswitchable. Cabs house 4 custom-voiced Celestion 12" speakers, handle up to 200W RMS power each, and have all the roadworthiness you expect from Marshall. Like all the AVTs, its preamp section is based on a 12AX7 and delivers great tone.