Rotel 1095 Amps & B&W802 = biamping make a difference?

[jazznsoccer]

Hi All,

I demo'd B&W speakers and settled on the 802's (higher up was beyond my point of pain for speakers). I really liked the 802's over the 803. Alll tests were done using the Rotel RMB-1095.

I've heard that most people would suggest getting a better amp, but there is that pesky budget thing to contend with.

Here's my thought:

Start with the 1095 and a good set of speakers (B&W802 fronts, HTM1 center and SCM-1 surrounds) to mate with Denon 5900. And try out the RSP-1068.

Go easy on cables (something like Tara Labs Prism 300i) and use 12 AWG speaker wire.

So the upgrade path would be either monoblocks for the fronts or maybe use the 1095 to biamp the fronts and get a 1075 for surrounds and rears for 7.1 down the road.

Anybody tried biamping with the 1095?

[Aussie Geoff]

Bi-Wire and save your money for a great Stereo Amp!

Jazznsoccer,

Rather than bi-amping with the RMB-1095 as your upgrade, I'd recommend considering bi-wiring the B&W 802s from day 1 (the RMB-1095 is set-up for this). The B&W 802s thrive on bi-wiring and in reality bi-amping is only a marginal step up.

Then, when you're ready for more you can go to 7 channels and get a dedicated 2 channel amplifier like the RB-1090 with its 380W into 8 ohms per channel for the 802s and still bi-wire. This is a dual mono-block amplifier with separate 1.25Kw transformers that is stable into the most difficult loads down to 2 Ohms and can produce 700W per channel into 4 Ohms and up to 1000W per channel into these lower impedences. There is no doubt in my mind I'd be buying one if I could afford the B&W 802s ! The B&W 802, 801 etc love high current...

Equally there are some other (non Rotel) stereo amps you could consider at the time (Parasound, Krell, Bryston all make some nice amps!) - but if you like the Rotel sound, I'd listen carefully to the RB-1090 - it's a real beast and one step up again for stereo from the RB-1080 which in turn is a step up from the RMB-1095!

Either way the dedicated 2 channel amps will do you very well compared to the RMB-1095, and bi-wiring is a real step up you can start with right now...

Geoff

[aud19]

Ditto and :drool:

I wish I could afford 802's a 1095 and a 1090 :E :P

That's totally the way to go, (including the bi-wiring Geoff recommended). The 1090 will soooooo make those 802's sing for movies and especially 2-channel! :drool:

Mike, where do you live? Cus I was wondering.... when you get all that gear... can I come over to play?!! ops:

:P :B

Jason

[jazznsoccer]

Hi Jason,

I'm in the LA area. It'd be nic to have some folks in the area to do some playing arond with gear!

[jazznsoccer]

Hi all,

I'm going to have to try out bi-wiring at some point. I really have a hard time rationalizing how this can make a difference since the wires are low impedance and low inductance and, by definition, are electrically common at the amp.

So, HTH, in technical terms, does this make sense? :wtf:

BTW the 802 manual recommends bi-wiring as well so I guess I'll have to audition.

Now bi-amping makes sense since any backsignals are completely isolated.

I thought about the 1090 and so am considering the 1090 + 1075 instead of the 1095 since I am most critical about music. But the bling gets louder. :hb

[Aussie Geoff]

Some info on Bi-wiring for you

Jazzmsoccer,

Re your bi-wiring query... (This reply is as much for others as it is for you, since you have taken the time to look at the B&W 802 manuals etc)

There's no doubt that bi-wiring is (for some) a controversial subject. Arguments rage in some forums ranging from "waste of money" to "the best single change I did to my system'. It is also often misunderstood.

To begin, Here is a primer article from Soundstage on bi-wiring and bi-amping.

To see a sense of the arguments out there (for and against) try this Hometheaterforum.com thread.

However, since you are going to be using B&W Speakers, let's see what B&W's Web Site has to say on the general topic. Factual and they recommend it....

As you point out, taking a look at the User manual for the B&W 802s here let me extract a quote.

Bi-wiring is the preferred method of connection and involves the use of separate cables from the amplifier to each pair of terminals. The separation of the signal paths improves the resolution of low-level detail and allows the user to optimise the type of cable to the frequency range of use.

Should you not want to bi-wire, perhaps during the initial set-up procedure or because you do not want to see a multitude of cables in the room, short cables are provided to link both positive and both negative speaker terminals together.

I hope this helps. Essentially - the manufacturer recommends it strongly for the speakers you are planning to buy, there are good physics reasons for it to work, and most people can hear the difference on high end speakers driven by very capable electronics.

Other than that I also think it is a little bit of black magic that works for reasons I find hard to understand!

Geoff

[Aussie Geoff]

RB-1090 vs RB-1080 vs RMB-1095 etc

Jazznsoccer,

I thought about the 1090 and so am considering the 1090 + 1075 instead of the 1095 since I am most critical about music. But the bling gets louder.

Loiking at your post in this thread where you compared the RMB-1095 to a Krell etc it is clear that you:
1) Already like the sound of the RMB-1095 with the B&W 802s
2) Understand the benefits of A-B comparisons

For me this will come down to a mix of your budget vs. your listening preferences vs. a sensible upgrade path. Let's look at some options:

RMB-1095 now with a 5 channel system (Retail Price $1999) This is what you heard and liked so you would be happy with it. You would upgrade later by adding either the RB-1090 or the RMB-1080 to the system and going 7 channel. (I vote for the RB-1090 as you know ) This is the lowest cost option now and has clear upgrade path that leaves the system balanced in sound quality between Stereo and Home Theater.

RB-1090 and RMB-1075 now with a (presumably) 5 channel system (Retail Price $1999+$999) This would give you the best Stereo right now with some (small) compromises for the HT sound. Some would say the HT system is unbalanced in quality with the Front Left and Right vs. the rest (but it's hard to match those B&W 802s anyway). Again you could buy the speakers for the extra 2 channels when you could afford them. There is also an upgrade path involving trading in the RMB-1075 for an RMB-1095 which you could lock in with your dealer.

RB-1080 and RMB-1095 now with a (presumably) 5 channel system (Retail Price $999+$1999) A number of HT Guide members have this system and are very happy with it, with their dealers recommending it for balance. Certainly I have the RB-1080 and it is a great amp for the money. You will hear the difference between it and the RMB-1095 (transparency and soundstage etc). However for an order of magnitude improvement - I have to say I know I would be trading in the RB-1080 after a while for that RB-1090 to get the extra edge with the B&W02s - so you'd better lock in a good price for this with your dealer if you take this option. Again you can buy the extra 2 speakers whenever you like.

RB-1090 and RMB-1095 now with a (presumably) 5 channel system (Retail Price $1999 + $1999). This is the “have it all now” system. But budget will be an issue presumably. Otherwise – why not!!!

Clearly – you have found a good dealer – so I’d discuss with him. I’d also A-B the options I was short listing for myself at the dealers – there is nothing like your own ears to help decide. If budget is an issue (and isn’t it always!) - knowing that you like the RBM-1095 on the B&Ws I’d probably take that for now and go straight to the extra RB-1090 and 7 channels when you can afford it. However to be sure you need to (at the very least) hear the B&Ws bi-wired on a (broken in) RB-1090 – if the difference says “buy me now” then you may need to consider one of the other options…

Let me close by quoting Azeke from another thread.

I also believe as elaborated on earlier, that a dedicated 2 channel amp (be it Rotel, Bryston, etc.) will solve your mid-range issues. I also thought something was missing with my original RMB-1095 setup in 5.1, and then I added the RB-1080, which enhanced my midrange and highs to a different level.

I find that the better the speaker, the more obvious the difference that a high quality, high current stereo or mono amplifier makes - and the B&W 802 is a very good speaker indeed. You may well find that once you have listened to the RB-1090 you can't go back.... Consider yourself forewarned

Geoff

[jazznsoccer]

Geoff,

Thanks for the research and detail - I really appreciate it! Fantastic job! :T

I remain skeptical about biwiring but have heard at least enough to do an a/b comparison just for the fronts. At this point, I'm going to put money in speakers and amps. I can play with upgrading cables down the road (got to save some fun for later :rofl: ).

Right now I'm thinking that I'll start with the 1095 since I do like the neutral sound and then audition the 1090 in a couple of months. After that maybe the extra 2 speakers.

Now any thoughts on whether I should make the speakers cables shorter and XLR interconnects longer or vice versa? Ideally, both would be as short as possible , but my gear rack will be about 15 feet away from the display and the fronts are about 14 feet apart. SO I could place the amp midway tucked behind the display or put the amp in the gear rack right under the pre/pro. :rollhead:

[Aussie Geoff]

I'd keep the RCA cables short and have longer speaker cables

Jazznsoccer,

Thanks for your feedback

Re your question regarding amplifier placement and speaker cable length vs. interconnect length - this is always a thorny question. General wisdom would have the RCA and similar connections between the amplifier and the processor the shorter with the speaker cables longer. Prime reasons for this relate to the lower level voltages and currents flowing across the RCA style cables (i.e. they are not yet amplified) - so these tend to me more susceptibly to noise and distortion through factors such as electromagnetic interference, or capacitance or inductance in a long RCA cable. And, of course, this distortion is then amplified and sent to the speakers. There is also the question of cost - with quality RCA interconnects generally running at a much higher price per metre than speaker cable of equivalent quality.

In my stereo days, I have personally used mono-block amplifiers to drive very difficult loads (large flat panel speakers and speakers with electrostatic tweeters) where it was better to connect the amplifiers as close as possible to the speaker to give it the best chance of driving it accurately. However we are talking some fairly exotic speakers and amplifiers here (e.g. Mark Levinson pre-amps).

However it is an interesting question and your new B&W 802s will represent a moderately complex load to drive.. Two additional sources of information that I would suggest:
1) Email B&W Directly - tell them you are buying the B&W 802s and seek their advice (www.bwspeakers.com) they tend to answer within a few days.
2) Post a thread on the Club B&W Speakers in this forum seeking peoples actual experiences with their B&Ws

Let us know the answer you get!

Geoff

[jazznsoccer]

Hi all,

Just for reference the kind folks at B&W referred this link when I asked about bi-wiring:

http://www.bwspeakers.com/index.cfm/fuseaction/local.faq/ObjectID/F5CA2780-3D20-11D4-A67F00D0B7473B37

Now that answered a lot of questions :rofl:

I think Oliver Stone should make a movie about the science behind bi-wiring. I'll start with basic good cable and talk my dealer into loaner cables to audition.

Geoff I also really enjoyed the forum link - lots of good debate. Thanks!

[pbarata]

Dear all,

Maybe this link from Linn can clarify a bit about the benefits of bi-wiring:

http://www.linn.co.uk/cust_supp/faq.cfm?CFID=22078&CFTOKEN=66899557#14

At least it presents a far simple quantitative explanation.