Need advice for B&W 804 diamond amplification


Hello all,

I purchased a pair of B&W 804 diamond towers about a year ago. At the time I purchased them, I also got a rotel rsp-1570 processor and a rmb-1575 5-channel amp. The rotel amp delivers 250 wpc all channels driven @8 ohm. Rotel calls this amp a true high current amp but doesn't list the current capacity in the specs. This amp is also a class D. I have lived with this amp for over a year now and have never really been satisfied with it. I have read alot of bad press about class D equipment in general. I hope to find some owners of the 804D here to gain some knowledge from. My main goal is to improve my 2-channel listening experience. I have set aside roughly 15k to upgrade with. I have done a bit of searching and I like the parasound JC1 mono amps and the JC2 pre-amp with the bypass option. This equipment is appealing to me because I have the B&W towers as part of a 5.1 setup. The JC2 would allow me to bypass the rotel processor and go to the amps during 2-channel listening. I could then switch it back for TV/Theater use. From the reviews I have read on the JC1 amps they seem to be good quality equipment that is in my price range. They are a class A/B amp but, they operate in pure class A up to 25 watts. I like to listen to my music fairly loud. Not enough to disturb the neighbors but still pretty loud. I'm just not sure how loud this would allow me to play without exceeding the 25watt class A operation. If I understand correctly, at the point it surpasses the 25w it then operates in class A/B. I'm not quite sure how that works. The B&W 804D does have a dual set of mounting post for bi-amping. I Guess to take advantage of this I would need either two seperate amps or a dual mono. would it be worthwile to purchase a stereo 2-channel amp and use it to bi-amp with or, should I just find the best mono amp that pairs up with these specific towers and use the included jumper cables. Another option would be to use a monoblock with a single output and run a cable that splits to four connectors and bi-wire them. Is there really any benefit to this over using the jumper cables that came with the speakers? I'm sorry for the long winded post. I am about to spend alot of money, atleast for me. I just want to make sure I am getting the most out of it. To make a long story short, If you owned the rotel Processor/Amp combo and the B&W 804 towers, what upgrades would you make to the system with a 15k budget? Please limit yourself to pre-amp,processor,amps,powerline conditioners and interconnects. I am not looking to upgrade source components at this time. All of my source equipment is pretty good. Thats another story for another time when I have more money. Thank you in advance for your suggestions and advice.

Andy Price
andyprice44
Amazing speakers ! congrats !

any high quality amp would be fine.

keep it at 250W or above. can they play with a 10 W tube thingy, sure, but why would you waste your time with that, those speakers are meant to rock n roll. !!!

Pass Labs
Threshold
AMPzilla


If you stick to some of the better brands, there is no wrong decision.
Let me first start off by saying these speakers are fantastic, I have heard great setups with the 804s. I will say in my experience I have not had great experiences with B&Ws and tubes, as a tube guy it was kind of disheartening. the best I have heard was dual Usher 1.5s and the 804s it sounded extreamly good. I bought the ushers after I heard that system and they have sounded fantastic with anything I have thrown at them. My main amps are the mc275s but I don't believe that would be a good pairing. The guy I bought my McIntosh mc7300 from ran that amp with 804s and he stated he had good results but I did not audition the amp with those speakers, I can say that any of my McIntosh solid state gear (mc7300, mc302) sound great with most my gear. As for biamping I've never had great results in doing this. One of the only times this seemed to workout decent was a pair of Polk Audio RT3000s and a pair of infinity RIS Betas I had a few years back.
Andy:

I have the system you contemplate. I use Parasound JC1 monoblocks with a JC2 preamp. I have used both B&W 804s and now have 803Ds. The 804s were actually quite good, with a nice sound stage and good imaging. Some sources can sound a bit on the bright side, depending on how the recording is mic'd (particularly silibance on female vocals). The 803ds have a better lower midrange and bass, and a larger soundstage as you can place them further apart. They benefit strongly by using a thick maple plinth with heavy brass footers, both below the speaker and between the plinth and floor/carpet. The plinth will really tighten up bass transients and provide resolving clarity all they way to the high frequrncies.

I did not find a dramatic difference between the diamond tweeter and the "s" version, in either detailing, air, or harshness. Some may disagree with me here. I almost could live with the 804 over the 803, since I use a powered sub (a HSU) in my system to supplement bass response. I think the diamond series does have better crossover components, however.
By the way, I should have mentioned in regards my first post, I have nothing against McIntosh, Classe, or Rotel, just tired of seeing that nearly every post on the web you can find on newer B&W speakers seems to involve these manufacturers, and I can not believe that people are not using something else somewhere out there (which is why I posted my lengthier post on my experience with the ARC gear). Also, I will note that I have owned Rotel in the past with great results, and actually heard the 804 D2's with Rotel's 70w/ch integrated and was very impressed.
I have the 804 Diamonds ("D2") as well. I have been evaluating them with my Audio Research 100.2 Solid State amp and Bel Canto Pre2 Preamp, which I highly recommend. While I have been listening I've been looking at other options in the event my 100 w/ch amp was not enough, and mostly out of curiosity really. The 100.2 is rated down to 2 ohms at 360 w/ch. In my research I noted that many amps were not rated below 4 ohms (per the B&W website the diamond speakers dip to 3 ohms). Anyway, after doing a lot of listening, and a lot of web searching, I'm not sure I want to change anything. The 100.2 is quite a fantastic amp, as many of the reviews here on Audiogon and elsewhere will tell.
One thing with the new diamond series is that the treble is very revealing, and I could see where it might get fatiguing with a bad match in electronics. At the same time, the ARC 100.2 is known for its treble quality. I have found that the two are an excellent match in that area. The ARC/B&W combination is very detailed while remaining crystal clear and not harsh. There is a slight warmth overall in the midrange on down, and I think both the speakers and the amp are known for this, and it is complimentary to the clarity and detail in the same range. Bass is very good. As an aside, I think people who criticize the bass on the nautilus series in general are not understanding what good quality bass sounds like...anyway, I digress...
If anything, I think if I needed more power I would just get another 100.2 and bi-amp vertically. The Bel Canto Pre2 is nice in that it offers two sets of balanced pre-outs, so you can do this. Overall this combination of preamp and amp is quite excellent – what would have set you back over $7k eight years ago can be had for about 2,500 now, and I think I would be hard pressed to do a lot better.
In the mean time I will keep listening and report back later. So far I have not even put the 804’s up on the included spikes, or Sound Anchors I bought for them, and still need to play around with position some more. But already they sound VERY good overall. Overall though I would say the ARC is a really good combination with the 804’s. ARC has some newer SS amps as well that are not Class D (such as the SD-135 and HD-220) that may be a good match as well. By the way, room size is 15’ by 24’ with 8 foot ceilings. I plan to move to a smaller space, which is why I bought these.
As far as frame of reference, I have never owned Classe but have had McIntosh MC-300 and MA-6900, and Rowland Concentra and Concerto. The MC-300 was very good with the Matrix 802’s I owned at the time. I would not put down McIntosh in any way, but personally I would not buy it new for the price. I would love to hear a Rowland Concentra II with these speakers. Otherwise, something like the Classe CA-2200 would be good to try, though some of their older amps (like the CA-101 ?) used for $700 or so also vertically bi-amped with a good preamp would probably get you a great value for the dollar. Some people have to have the latest gear, but it seems a lot of the older amps from many of these manufacturers have greater power/current down to 2 ohms, while the newer models are not rated at 2 Ohms. Not sure if it really matters, but having owned several pairs of B&Ws over the years I have found it true that they really seem to open up with more power.
Hi Andy,
There are many worthy options in your quoted price range.

I own the 803Diamond, and previously the 803D and 804S. I currently use a Classé CA2300 (300W stereo) amplifier, and previously the Cambridge Audio Azur 840W (200W stereo) bi-amped.

I can highly recommend both amplifiers - the CA2300 is more precise and transparent, particularly in bass/mid-bass whereas the 840W has a slighter sweeter mid-range. Both amplifiers run a few watts Class A mode before transitioning to Class AB. Both amplifiers are superior to the very good Marantz Class AB amplifiers I have previously used. My conclusion is that Class A is desirable and the benefit of the resulting warmer/sweet tonal sound quality is obvious through the B&W Diamond tweeter and midrange.

The Classé CA2300 is overall a good match for the 803Diamond (and should be with 804Diamond). The 840W is bargain given the sound quality, but note there is a replacement due because it was recently discontinued.

I once precisely measured how power I used for typically music listening sessions and was surprised that it averaged a few watts(!) with a peak of around 40Watts when I very occasionally turned the volume up. So you can assume that for moderate listening sessions that 25W Class A will be more than adequate.
However for home-theater you need more Class AB power - I haven't measured peak power in my home theater - but I guess aim for 150W or greater.
Do consider the amount of heat generated from a full class A amplifier (e.g. Pass Labs XA100.5) in a confined home theater room.

I am big fan of bi-amping – it will allow lower power amplifiers to sound less stressed (greater headroom) – the primary benefits is improved sound-staging with more precise imaging and delineation between instruments. However a superior amplifier is better than a two lesser quality bi-amped amplifiers because instrument tonal quality is more critical than sound-staging for long-term listening pleasure.

The Pass Labs X.5 series and Parasound JC1 amplifiers should be auditioned based on their consistent good reviews. The McIntosh is a favorite choice on the HTGuide B&W forum. Unfortunately I have no personal experience with these amplifiers.

Regards
Mark
Thanks for all the responses guys. There is a Hi-Fi shop that is in a bigger city about an hour away. They deal Mcintosh gear. I am going to see if they have any demo models they can loan me for a home audition.
I Think I am going to stay with SS amps. I like the idea of using 2 of the MC252 for Bi-amping. The specs on the MC252 also state it can be bridged mono. I sure would like to try this model out in my system. Now I just need to get out there and listen to some amps.

Andy
I've heard them with Pass Labs and Bryston. Both were pretty good. Pass was the better of the 2.

As far as why Rotel and Classe, I believe B&W owns Classe and I think Rotel too.

Not sure on McIntosh, that could be one of those coincidences.
B&W - it's ALWAYS Rotel, McIntosh, and Classe. Why is that. Hmmmm...every dealer I've ever been to that sells B&W sells either Rotel and McIntosh or Rotel and Classe. Has anyone ever tried with another amp?
I don't have 804D, but 804S. When I upgraded the speakers I had a Rotel RB1080 amp, which worked great with lesser B&W, but wasn't on par with the 804S. I auditioned some amps, narrrowed down to Classe and McIntosh, preferred Mc, and ended up with MC275 (tubes) over MC252 (SS). I really like tubes with my speakers (later got a tube pre).

At the time I was auditioning for amps I did listen to a pair of 802D driven by huge VTL (tube) amps and the sound was outstanding too.

With 15k you could even buy 2 MC275 and try them as monoblocks or to biamp (I myself would love to listen to that!). Or if you preder SS 2 MC252. Classe is also great. Rowlands are said to work great with B&W too, but I haven't heard them. Have you checked the audiokarma forum?
How much do you want to spend max.? The best use of speakers that good is strictly 2 channel for music.
Movie sound tracks do very well with fairly inexpensive speaker sets with a good sub for LFE which means low frequency effects.
I would seriously consider separating the two systems.
thanks for the suggestions. sorry for the poor indentations, I was typing this out on my phone.
1st suggestion? Learn how to use paragraph breaks - your post is virtually un-readable.

As for amps, you should *seriously* consider the Butler Monad A-100s that are for sale here for about 1/2 retail. These are incredibly good amps (Class-A, 100 watts!!) and will make those B&Ws *sing*....

http://app.audiogon.com/listings/butler-audio-monad-a100-mono-amps

http://butleraudio.com/esoteric.php

-RW-
Well, you said you like the Parasound, so why not go for that?

There's a lot of choices out there. A few are; Pass Labs, Accuphase, Bryston, Sim Audio, and Ayre.
Does anyone have any suggestions? Are there any B&W 804D owners out there.... Please help me out guys.
I have the 804 Diamonds, use Musical Fidelity pre-amp and amp (M6PRE and M6PRX), and enjoy the result; however, my situation is strictly 2-channel. The amplification brands that I see discussed most frequently as good pairings with B&W are McIntosh and Classe.