Biwiring?

That link is a mixture of circuit analysis and pseudo-science. First, the pseudo-science:


"What does this sound like? Well, usually, just as you may expect from physics, it appears as a change in the reproduction of space and sound stage. Often, the first impression is that the "biwired" sound presents extended "dimensions", more "air", and is more "living". The impression after a week or month, however, is that all recordings sound very much alike, and the "airiness" appears on all records. It does not even sound like air anymore, instead more like a slime that pollutes every record you play. No wonder, since it is not a real, recorded quality but a "speaker characteristic" added to all reproduced material. "Sameness" is another word for it."


I would not expect from physics to hear a change in the soundstage. I don't know how I could physically analyze anything to do with "soundstage," as there does not exist even a physical definition of the term.


As for the circuit analysis, he uses a lumped circuit model for the cable of 50 milliohms in series with 8 microhenries. This is a pretty good start, but 50 milliohms is a little high. However, the resonance of the cable inductance with the capacitance of the crossover contributes a paltry 3 degrees of phase error. This phase error is dwarfed by the phase errors inherent in the speaker. Furthermore, the circuit model used is simply wrong. The models of the low and high frequency drivers are grossly oversimplified, and the cable should be modeled as a distributed network, with per unit length elements. Using a better model would wash away that phase error.


Anybody that reads that website with their bullsh*t detector turned to the ON position will have alarms going off.


Tim

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There are other threads about this, and you will get all sorts of recommendations, but based on MY experience (YMMV):


1. Passive bi-amping is fine, go ahead, have a good time, just don't expect miracles.


2. If you want miracles, you have to go active. HOWEVER, unless this is something you're doing for pleasure while you're not at your day job as a speaker designer, don't do active xovers unless the speaker is designed with them in mind. Get some speakers that are already active, or use something like Linn, which provides active xovers for their speakers and a mechanism for disabling the passive xovers.


Most important is taking the passive xover out of the circuit (and surely voiding any and all warranties if the speaker isn't intended for this treatment). If you ignore this and run active/passive at the same time, you will succeed in making your speakers sound different, and you will, for a while (duration determined by your emotional investment in the outcome) convince yourself that you've succeeded in improving the speaker. After some time, you'll realize that you've wasted time and money.


Claude

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Tim,


Upon a more deeper analysis of this artical, you are exactly right in at least one context. In the larger scheme of things, a 3 degree phase error is very minute, especially with the phase errors of the drivers as well as the driver/listener placement.


Since this is a simulated analysis, a better solution would be to do an actual anaylsis and measure phase/frequency differences between biwire and single wire configurations. I may do this sometime in the future when I have a lab setup.

This is from a response I posted in the Remote Central Forum a year ago, when someone asked about bi-wiring vs. bi-amping:


About bi-wiring, there would be no effective crossover differences. As for bi-amping, the reduced loads on the respective amp sections would be beneficial. However, the ideal bi-amping situation would include an active (i.e., in the line-level stage, between pre-amp and amps) crossover, which presents its own caveats:


The crossover components within the speakers should be bypassed, i.e., wires run directly from cabinet terminals to driver terminals, because:


All amplifiers not only start the driver diaphragms into motion when fed an input signal, but also control and/or stop such motion when the signal changes/stops. This ability is determined by the "source" impedance of the amplifier's output stage, and is typically known as "damping factor". Yes, sources have impedance ratings, just like loads do. Source impedance is the ability of a source to not be affected by the load, which is why a larger power supply (or battery) will drop voltage less than a smaller one with increased load current.


Solid state amps usually have a very low (