How different between B&W 804s & B&W 805s????

I know that floorstanding speakers always better than the bookshelf...

I don't know what has made you think this but that is not necessarily true.

What you can expect is a fuller sound with the 804S as they have more bottom end to them.

Which to upgrade first, speakers or amp, would be your call; what is your current amp?

thanks for your response. Yes i want fuller sound and more bass .That's what i mean better :-)I'm using Marantz Pm14MK2.

"I know that floorstanding speakers always better than the bookshelf..."

Second Brianmgrarcom, Not necesarily true. Mate your 805s to a high quality subwoofer that integrates seamless (e.g. Rel) and you'll get dynamics at least as good as the 804's if not better, and even a fuller sound than the provided by these floorstanders.
Jov

I'd actually prefer upgrading to the 804S over adding a sub, but I haven't had much experience with subs and the little I have had wasn't great.

The advantages of stand mount speakers, usually, is their ability to disppear, at least better than floor standing speakers.

I have only heard the 804S once and I liked it; having owned the Signature 805 I felt the 804S reminded me of the Sig 805's with added weight; I also have a friend that has 804S speakers and is very pleased, he also owned the Sig 805's with a sub, he prefers the 804S.

Brian