It is my opinion, B&W speakers sound best (as with most speakers) with an amp that has "jump" factor to it. Amps in my experience that play dynamically are:
Mark Levinson #27.5
Fully restored (recapped) by authorized repair center, George Meyer in Los Angeles. This amp is for sale here:
https://www.georgemeyer-av.com/mark-levinson-no-27-5-dual-monaural-power-amplifier/
This Mark Levinson integrated amp, #383 also on Meyer's website (fully refurbished) would also be a great choice, considering the $3,000 dollar cost.
It is located here:
My last suggestion is this Esoteric A-02 amp being sold at The Music Room (TMR). They want $6,000 dollars for it. This is a beautiful sounding amp; I know first hand as I currently have one of these. 400 watts into 4 ohms! These will make your B&W's play with some dynamics. It's a heavy, but manageable beast at just under 100 pounds. It is located here:
