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

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.

several years ago, when I first got bit by this hi-end bug, I got some BW 602's. naturally, the quest for better set in and soon I was auditioning older series BW matrix, the 805's and 804's. I settled on the n804s' and loved them for quite a while until the upgrade bug bit again. At first, I tried to run them with a HK AVR 500, an 85watt, high current home theatre integrated amp. It was ok at low volumes but clipped at too much volume. I lucked in to a Classe CA300 amp, matching CP 50 and CDP .5, they really made those speakers come to life. Now, on the other hand, I heard the 805's driven with great equipment at the dealers and frankly, I couldn't believe what they were asking for them, I found them to be no better than my old 602's. my 2 cents.
jb

I have the N804 in a second system and the N802s in a reference system. I have also owned the 602 Series 3 speakers.

Before I picked the N804 I auditioned the N805 in my house for about two weeks. This was many years ago. The N804 is fabulous speaker. I think it is better than the N805 in every way. This was some time ago but I remember making a serious inquiry into whether the N804 was just a bigger N805 and the conclusion I came to was that in addition to the larger cabinate and lower range, the tweeter, midrange and crossover units were supposed to be better. It is not just a taller N805.

If you like your N805, you will probably like the N804 better. Basically, the sound of the 804 is a fuller 805. The difference is not insignificant, however. More bass is always significant.

Let me tell you what the problems with the 804s are. I have used them for 10 years, and I know them well. This is totally subjective. They are absolutely unforgiving when it comes to revealing the source. You NEED warm, refined components with these speakers. They are not inherently bright, but they can be quite hard on the ears with bad recordings.

Another problem is that, even though the 804 is a lot fuller than the 805, which only goes down to 49Hz, the 804 only goes down to 38Hz. This is a big improvement over the 805, however, this is not the type of speaker where you are going to simply call it a day and be happy that you have enough bass. At some point, after the honeymoon wears off, you will want even more bass. The 804 is a little lean in that sense, and you will eventually run into the same issue you are having now with the 805.

For that reason, I do not recommend the 804 as an upgrade from the 805. If I were in your shoes, I would save for the less compromising 803S, which gets down to 35Hz and in my experience is a more satisfying speaker. I feel like, since you have been compromising on bass for so long with the 805, you should move to a bigger floorstander than the 804.

I love my 804s--everything they do they do very well. They simply do not go deep enough in the bass for them to be an endgame solution.