The treble and bass adjustments won't do much damage to the overall tone because decent amp companies like CA, NAD etc.. design them to work at the frequency extremes.So if the music you are hearing does not have much extreme info, it can't do much.This is a good design principle but poorly understood by people used to tone controls found in Japanese amps.
I think the Nad 320bee would have been a better choice because it has been measured to have almost 80 watts per channel although it is speced to 50 watts.I tested it once with my inneficient speakers and it drove them better than a 100 watt nakamichi amp.