Where is the bass on my B&W 802d speakers?

BHK Preamp Review

The sound of the BHK Signature was incredibly smooth. Everything I played through it had a palpable presence that washed over me like a slowly moving stream -- no pressure, no haste, no fatigue, just music. Voices emanated tangibly from the soundstage, easy to pinpoint in space

OP, FWIW, I took a few moments to read some of the reviews on your amp and pre-amp. In the reviews I read they were given high marks, and a reader might logically assume that they might be an excellent match. Since I haven’t heard them, I cannot agree or disagree.  But IME synergy between electronics and speakers is critical. Whether or not this synergy exists cannot be determined until you have maximized the speaker/listening position for your speakers. Obviously if the electronics’ are not a potential problem there are only two other options, the speakers themselves or (most likely) how you have set them up. How you approach this problems solution is up to you. 

Good luck.

jeffbij had some great advice.  I am sure that either your chair or those speakers are in a bass-null area of the room, there's really no other explanation.