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

I previously owned the 804S before upgrading to the 803D. Unfortunately I haven't directly compared them to the 805S, so cannot comment on 804S vs 805S.
But I do want to comment on the 804S and 803D given some of the posts above.
The 804S is a very open (definitely not congested or boxy) high definition loudspeaker that remains composed at surprisingly high volumes. While it performed well on modest Marantz gear (SR9300, PS17SA, SM17SA), the overall tonal balance was a light in my large open plan lounge.
The 803D is all round improvement (midrange a bit more laid back than the 804S), but much better bass and tonal balance. And contrary to a post above, the driver integration is superb and noticeably better than the 804S which was not bad. Surprisingly the 803D is not as demanding on amplification as the 804S, but does responds to every improvement up the chain.
I did try the 804S in a small room (3m x 3.5m) where the bass tonal balance was good, if not earth moving.
My suggestion is to compare the 804S to 803S to 805S+subwoofer with your preferred amplification before making a decision.
BTW, the Marantz PM14Mk2 is a great amp and will drive the 804S or 803S/D fine.

Thanks.. in the meantime I had a chance to compare 803s and 804s and I am sold out on 803S. The question remains on compatible electronics with the speakers that supply good power - I am going to try Marantz and Macintosh equipment over the weekend based on the suggestion. Hopefully I move closer to making a decision.

Cheers!

Vikaschhariya: I run a pair of 803S' with a macintosh 402. I compared a number of amps (however not any Marantz models) and nothing came close to the mac for my tastes. However, I herard little, if any, difference between the 252, the 7000 integrated, and the 402. In pushing the 803s' to their limit I could get the power guard lite to flicker on the 7000 and 252 - which did not happen on the 402. Speakers are a matter of taste- I like the B&W sound and compared the 805, 804, 803S&D, and 802 - and from my perspective the 805 and the 803S were the best of the lot. The main difference I noticed between the 803S and the 804S was the 803S sounded better at low spl levels than the 804S. While his goes against the conventional hype - I did not like the sound of the models with the diamond tweeters; if B&W currently had their metal tweeter in the 802 model I would have went that route. Good choice on your speakers - let us know what amp you choose.

Musicnoise, interesting stuff. Did you get a chance to hear the McIntosh MA6600 at all?

Brianmgrarcom : No I did not get a chance to hear the MA6600. I did listen to the 6900 and found it a little lacking in power, i.e. turned on the power guard easier than the 7000 or 252. Kind of an interesting experience actually. The store that had the 6900 apparently had an ac power feed with poor contact or some other deficit - it is the only time that I saw the room lights dim anywhere, other than due to high inrush current at power up. When the 6900 drew enough current to get the 803S to about 105 db Spl (and yes I do carry an spl meter with me when auditioning speakers) the room lights dimmed. Now I know from putting a meter on the 402 that about the most that is drawn at those spl levels is 6 to 7 amps - which never causes dimming lights or any other unwanted effect and I run the system off of 40 year old wiring.

However, I will say that the, to me, the 6900 sounded pretty much the same as the other mac amps. From my experience the macs have a different sound than other solid state amps - probably has to do with the inductance of the autoformer - I know mac says they are accurate and the specs are incredible - but for whatever reason, they do sound different . Obviously, I like the sound and would not go elsewhere. By the way - nice system - I run the C45 rather than the C46 but it was a tough choice between the two. How are those watt puppies? What is your descriptive take on those as compared to the B&W's (any model) and what music genre ?