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

The 805s sounds ok to me until one day i heard it driven by a McIntosh 6900, i realize this is what my speakers need and i'm saving money for this amp now. I can't stop thinking about it :-).
You guys so lucky living in U.S where you can borrow amp, cdp bring home and testing with your system. NOT LIKE MY COUNTRY. Thanks you so much for your advices... I also like the 804s. Its second hand but few months used only. The importand thing is it's a nice price. My room size is only 12sqm(3mx4m. Btw does anyone here using NORDOST interconnect, speakers cable with B&W??? How's the result???

About six months ago I heard three S series side by side with a nice McIntosh setup. They were the 805, 804 and 803. It was at a dealer and the room was not good but remember being really impressed with the 805 and 803. Both of these blew me away. The 804 didn't do it for me. They seemed congested compared to the other two. Again, it could have been the room or general setup. All great speakers.

Given the size of the room, I presume you will be placing your speakers along the long wall. My opinion is it is more worthwhile to upgrade your Marantz integrated amp to the McIntosh rather than going from the 805S to the 804S. I believe the 805S is quite ideal for your smallish 3mx4m room which is about 10'x13'. The McIntosh will give you a fuller sound and tighter bottom-end that you seek. If you find the bass to be still lacking you can always add a subwoofer after that. On a separate note, since you have a dedicated room it would be good if you can work with the room acoustics. You can be amazed at the sound improvements with proper room treatments especially for small rooms like yours.

Thanks everybody for sharing your experiences. I think i will keep this 805s and earn more money for the new McIntosh 6600. I heard this one is better than 6900.
Does anyone using Nordost interconnect with B&W speaker? Give me some reviews please.

Ngocdj: I run my main system with an MC402 and, for my ears , there is Mcintosh, and then there's everything else. You mentioned the MC6600. One thing to check on is whether Mcintosh uses their autoformer with that model. I know that Mcintosh did, at some point in the last few years, sell an amp that did not use their output transformer or 'autoformer' . It is my opinion that the sound you get from the mcintosh amps is influenced by the use of that autoformer - This I have not verified mathematically - mainly because I do not know the electrical specs of the autoformer and have not bothered to find out. Personally, though unsupported in this matter by any analysis, I would stay with a unit that uses the autoformer. Just something to think about.