I believe Musical Fidelity is known for a more neutral sound rather than a meaty, robust, non-thin sound. I could be wrong. The power rating does not in itself give an indication to the fullness of the amp's sound. You don't need to go to tubes for this.
Another member recently wrote of matching a BAT preamp with a Bryston amp in this thread. Bryston's are very neutral and accurate amps. The BAT added some welcomed warmth and fullness for the member who paired the two. A BAT preamp might be worth investigating.
Another member recently wrote of matching a BAT preamp with a Bryston amp in this thread. Bryston's are very neutral and accurate amps. The BAT added some welcomed warmth and fullness for the member who paired the two. A BAT preamp might be worth investigating.

