The PRO TUBE IV delivers 400 earth-shaking watts of power. Channel 1, has a unique two tube preamp featuring a 12AX7 paired with an EL84 power tube. The power amp is switch selectable from just the 12AX7 or the 12AX7 PLUS the EL84 for that unmistakable power tube distortion. The Crunch control takes you from ultra-clean maximum headroom to a juicy tube overdrive. A group of three position switches shape the low, mid, and high characteristics of the sound. A contour switch applies a Warwick voiced, "smile" curve. The second channel of the PRO TUBE IV amp head is all solid state with a switchable limiter and enough bands of graphic EQ to dial in the perfect sound in any room.