50 w/ch is not enough for those speakers and the lack of low end punch is the amp running out of power. Until you put something behind them with some power, they will not give you that nice bottom end. These are not efficient speakers, about 83db/w.
I ran a set years ago and a Hafler DH-220 was just adequate. A pair of NAD 2100s run in mono 150w/ch continous, 600 peaks) woke them up. By comparison, my Magnepan SMGa speakers were easier to drive.
I ran a set years ago and a Hafler DH-220 was just adequate. A pair of NAD 2100s run in mono 150w/ch continous, 600 peaks) woke them up. By comparison, my Magnepan SMGa speakers were easier to drive.