I have a pair of the B&W 684's as part of our home theatre system, and they are a nice pair of speakers (although I think the weak link in my system is the Denon HT receiver AVR 2807 - it has a very lifeless sound). I suspect my speakers are underperforming on this receiver. We also have B&W Nautilus 803's on our music listening system, and while they are very different speakers, I would describe the B&W sound as a warmer type of sound.
However... someone else mentioned Focal speakers. We bought a pair ($1500 for the pair) of the new Focal Chorus Prestige series 807W paired with a small Rotel integrated amp for our vacation home. I have been stunned by these speakers. I absolutely love the sound that comes from them. Someone commented that they thought Focal was too bright, but I would strongly disagree, and instead I would call the sound from them as very crisp and lifelike (not shrill at all). Vocals sound amazing on them.
I have been a big fan of the B&W sound, and I do love our 803's but the sound from these much cheaper Focal speakers is quite remarkable. I strongly recommend you give some Focal speakers a listen to... you might be very pleased. I could not be happier with the choice we made.