Biamping B&W Nautilus 803's

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.

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.

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

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'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