The 14b is way too much amp for the 804s. I was able to pop the woofers on the 802s with a 4b. Bryston makes excellent products. Go for the 4b. By the way, the preamp really makes a bigger difference on the warmth of the sound than the amp. Go for a tube pre with the Bryston amp. Really, most of the 14bs power will be just wasted on the 804s. I have 6 pairs of B&Ws and 2 Brystons so I have a lot of experience. E mail me if you want to talk more.