Biamping B&W Nautilus 803's

hi there, I’ve seen forum message and deside to wrihgt ...I have got b&w803s and would like bi-amping connection but don’t know if its possible...
I have macintosh mx150 as processor and quadro-mono ATI3004...mac has additional regulate outs for biamp but mx150 hasnot needed 350hz for 803s
and sound was with holes...please tell me is it possible remove passive crossovers inside b&w803s?? how many this crossovers it has? 2 or 3? I opened this one and can see only 2..but in the B&W papers I can see 3....please understand this situation if possible to me....I tried connect to macintosh but didn’t understand a little))
many thnx)
vlad
ps sorry for brocken english)

Since the cross-over is a high 350hz your best bet would be identical amplifiers.

I like to add something here. I started experimenting with bi-amping about 25 years ago and I know you get much better results(by far) with active Bi-amping or active tri-amping. The headroom's gain and the control of the amp over the drivers is not comparable. To do this, You have to know what you are doing and be able to afford it too. All the passive components must be removed and the crossover curve, the frequency points and the power to each driver must be experimented with(with out blowing the tweeters). I have build tons of passive crossover and I know active is the way to go. I have a very good example to compare these two. Passive is like having a 4 wheel drive car with two smaller tires in front and one engine and 3 diffrentials working hard to disturbute the power to all four wheels. Active is like having 4 wheels with their own engines and a computer governing all four engines in real time.

Welcome. It looks like that from your profile you've just arrived. A word of warning. While this isn't like Yahooligans you may get flamed over your premise that biwiring doesn't do anything. I guess I'll be the first. Sorry. B&W make it pretty clear that they expect the normal hookup to be via bi-wiring. Some folks around here use completely different wires for tweeters vs. mid/bass. Thinking about it my bi-wire setup has silver for the upper frequency and pure copper for the lower. Guess I went a little overboard on that one. I'd love to bi-amp, and am sure it would make a difference. But it would make a difference to my wallet, my relationship with my wife (she'd notice another box, honest), just to improve the sound on a system that I already enjoy daily.

By the way my power amp seems to deliver anything that's necessary, including heat (I'm in Tahoe and it's damn cold right now). But it would be nice to use quality power to my mains by using 4 of the 5 channels.

Again, welcome.

Hi there! Bi-wiring and Bi-amping is one of those items that everyone swears over, either in favor or against. Physically, if you bi-wire (two wires from same amp connection), then you cannot create any difference, because the response required from the amp is the same as with one set of wires. Bi-amping is supposed to allow separate transients to flow to the separate amped parts of your speakers. I don't care what anyone says about B&W's use of less wattage. If you want to hear your speakers sing, give them (almost) as much wattage as you can. For that reason alone, unless your amp is pushing 400 watts per channel, bi-amping (not bi-wiring) should really help. This is just my opinion, of course, but I've been listening and using B&W speakers for the past 20+ years, and there is nothing like them in the world - if they have enough power!! If you need to talk more, contact me at gkbatc@aol.com.

I've seen them but they're rare. Quest for Sound has them on this site, I imagine there are others..

http://www.audiogon.com/cgi-bin/sh.pl?0&1&adlr&Questforsound&home&

Greg

http://www.bwspeakers.com/service/getthemost/ has a section on bi-amping and http://www.bwspeakers.com/service/faq discusses changing the internal crossovers (i.e. disabling them) as well as introducing active crossovers. Note that they almost dictate that you should bi-wire even though they provide jumpers but warn of difficulties beyond that.

But I have N803s too. And wouldn't it be nice to bi-amp ? I was thinking of using 4 of the channels of my 5 channel amp (Pass Labs X5) for a passive bi-amp of the N803s and the last one for my HTM2 center, bi-wired. Then a separate, cheaper, stereo amp to run the Signature 7NT surrounds. Trouble is that I've got balanced connections and I haven't seen Y's in this config, other than cheap microphone type wires. Anyone have any thoughts ?
Andrew

I would give it a try with passive bi-amping and see how it sounds. The benefits with a passive bi-amp include: increased power, improved damping and keeping the back EMF from the woofers with intermodulating with the upper frequencies. Plus, if you decide it isn't worth it after listening, you can go ahead with the sale...

If you like the sound you can employ an active crossover as well, either with your passive crossovers in place, or for the best effect, by removing them.

Greg

While I cannot argue the benefits of defeating the internal crossover and replacing it with an active crossover, I can say that bi-amping using the internal x-overs will work and provides noticeable improvement. Provided, of course, there are two sets of binding posts on each speaker. If this is the case, when disconnecting the "shorting bars", the lower connectors feed through a low pass filter and the upper connectors feed through a hi pass filter. I do this with Dunlavy Cantatas and two Aloia power amps.

I have never tried an external active crossover so I can't state that one is better over the other. One might assume that an outboard, dedicated, more expensive crossover may be better but you can try it using the speaker's filters alone first. Experiment then with the active crossover.

For me, immediate sound stage improvements, more detail resolution in the mid-hi's and more control on the woofer.

If you will make it with literacy and with knowledge of that issue you might unbelievably succeed. I've had a previous discussion and also read some theoretical bases of successful biamping and reveal to you what I'm currently aiming for:

Having a second amp is great but not good enough. You have to acquire in addition an active crossover and disconnect the built-in crossover(s) from the speaker otherwise a bi-amping will be just a waste of money(don't plan to do a passive bi-amping with all that Y-connector kind of softly-saying excersise since it's the same thing as to have one amplifier).

In my future plans is to get either top-end amplifier with smaller power than I currently have or the bottom-end amplifier with larger power than I currently have and certainly active crossover or DIY kit with top quality parts from Marchand Electronics or Percy Audio.

The outcome might be drammatically great for speakers and for amps as well. Due to a simplier path through the drivers the amps will drow a higher current without clipping; due to a drammatically lowered inductance of active crossover the higher freequencies will become so well defined and less fatiguing.