I also agree with PBG's comparison of SVTs vs. 400PSs--I've got an old SVT, an old V-9 (the 300 watt guitar counterpart to the SVT) and a recent SVT-300 (tube amp only, no preamp stage) running with an Alembic SF-2 & an F-1X). All sound different to my ears...I do like the 400 PS. Unlike a Bassman, note that the "Normal" channel is like the the "Vibrato" channel of a 60s blackface Twin Reverb with reverb, speed, and intensity controls (uses the same footswitch of a Twin, as well).