Muralman: You are 100% correct. THe X600 Passlabs monoblocks do have 4000kVA toroidals. But unless these monoblocks are running on 230 volts, its useless. If the X600's are running on 110 household current, its not going to matter if its a 2000kVA,3000kVA or 4000kVA toroidal. For the x600's to run their very best and put out their best dynamics they neeed 230volts. The palladiums were designed to 100% maximise basic 110volt 20 amp lines and no more. As for capacitance, the x600's have 180,00uf per side, about 20% more, but again its needed, especially if your on the heavy juice. As for the biasing for class A, the Palladiums actually put out a bit more than the x600's in this configuration across the impedance range. Dont get me wrong, the x600's and x1000's are one of my favorite pairs of SS amps, but there is no denying how close both amp pairs are in terms of power and SQ in reality. I would give the x600's the edge for powering a pair of inefficient 1 ohm speakers, but thats a really small edge, especially if your on 110volt juice.