Yes, I sold my Atma-Sphere MA-1 amplifiers. As it turned out, I didn’t have a great match between my passive pre-amplifier and the MA-1’s, as the MA-1’s need alot of voltage (3V) to push them to their fullest. Solo acoustic music sounded fantastic regardless, but more complex pieces seemed rather condensed and muffled. Since then, I have tried three or four other amplifiers, all of which have had their strengths and weaknesses, as outlined in previous posts. Currently, I’m using Ypsilon Hyperion hybrid amplifiers to drive the Sound Lab speakers. My opinion that has developed is that the more power you can give the speakers, the better (200-400WPC).