The minimum and nominal impedance of the speakers is a major factor in determining the suitability of OTL amp. Without this info it's impossible to offer an opinion, IMO.
With 91dB speakers, the room size and the volume at which you typically listen are also important factors considering the 60wpc output of the M-60 amps.
With 91dB speakers, the room size and the volume at which you typically listen are also important factors considering the 60wpc output of the M-60 amps.