I had a 4B-ST in use for mastering applications as well as critical listening and I can tell you without reservation that the SST amps are superior in EVERY category. If you want an amplifier to color the sound in any way, look elsewhere. If you want an amplifier to give you stellar resolution AND pack a wallop without flinching, get a Bryston SST. I am very pleased with my 4B-SST and have no desire to upgrade. The 4B-ST is a great amp. The 4B-SST just takes everything to a higher level.
