Hi,
I have a NAD C370 which I use with B&W 603s3 and it does a great job with rock and reggae, loads of bass and good fun to listen or jump around to !!
I have also used my Alpha 9 with the same speakers which is a slightly warmer, laid back sound but this could be an option but I think the NAD would be the better route.
I found my Caspian a bit too harsh with them but gave a huge sound but heard it with some 684's and ended up buying the amp.
I like the 684's as I think they are better than my 603's not quite as harsh in the treble and being a large design they fill large rooms very well, for your taste I don't think you will be disappointed , your neighbours might be.
Good luck and have fun.