Do you Bi-Wire, if you can?


This topic came about in another post.

If your speakers allow for bi-wiring, do you use this feature? Or, do you use good quality jumpers and single wire cables? Or, do you just use the jumper plates that come with the speakers and single wire cables?

(If you are bi-amping, then that's completely different.)
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Showing 5 responses by bombaywalla

yes, my speakers allow for biwire. at the start I used a single pair of speaker cables + jumpers. The sonics were good.
Then, when I had some money, I bought a 2nd pair of speaker wires & did a shotgun run of 2 pairs of speaker cables per speaker. The sonics were vastly improved in the bass region. on this account i'm seconding Mattmiller "Two sets of runs always tightens things up!
Mattmiller"
In my case it was very apparent & successful. I won't be going back to a single pair + jumpers. FWIW. YMMV.
09-23-15: Mitch2
It sure would be easier if there were "standards" in the audio world, like providing only a single pair of binding posts on speakers.
Mitch2, there cannot be a standard in audio for providing 1 or 2 pairs of binding posts on a speaker because cross-over design is not a cut-and-dry process where every manuf will have the same circuit. Cross-over design is complicated & full of trade-offs (such as rapid response decay & good transient response). Each speaker designer is going to choose a slightly different set of compromises that will result in a different cross-over circuit & a different sonic signature. The way the cross-over circuit is designed will have a large bearing on whether the speaker designer want the cross-over to "see" the low impedance of the amplifier (parallel cross-over topology) or to "see" the impedance created by the other cross-over elements (series cross-over topology). In the series cross-over topology the designer might not want you messing with 2 pairs of speaker binding posts that changes the impedances of the cross-over connected to the various drivers - he will want full control of this by ensuring that the signal comes in at one point & then fans out into his cross-over with controlled impedances (by his selecting the value of L or R or C per his calculations) at each node.
Cross-over design is art + science & many compromises to the final result. There can be no standard when such is the nature of the problem.
Perhaps not, and of course there isn't a standard, but the amplifier output originates from a single positive pole and a single negative pole. Therefore, assuming only a small L/C/R effect from the speaker cables, is not the relative current draw at each crossover board determined by the drivers and crossover components and not whether it arrives at the speaker by means of a single pair of positive/negative wires or two pairs of wires in a bi-wire configuration?
Mitch2
Mitch2, it's not as simple as you make it out to be. Yes, current is single-ended when it comes out of the amplifier (altho' several Ayre amplifier designs are fully differential outputs) but it's not just running current into the speaker x-over. It's also a lot to do with the impedances the x-over circuit creates & whether or not the speaker designer wants to introduce a highly variable parameter from the speaker wires (it's R, L, C) & the amplifier output impedance (remember tube output impedance is much higher than s.s. output impedance. thus tube amps have a different effect on the x-over than s.s. amps).

A picture is worth a 1000 words. take a look at these pics that I've uploaded for you viewing. These pix are courtesy of Arthur C Ludwig Sr - from his article on this subject.

https://picasaweb.google.com/106074825717940223133/SpeakerCrossOverCircuits?authuser=0&authkey=Gv1sRgCLa8tuTSmPLALg&feat=directlink

if you are using a parallel x-over topology it's easy to see how we can have 2 pairs of speaker binding posts.
What happens when we use the series toplogy? How do you break that circuit & provide 2 pair of binding posts? And, the speaker designer can definitely decide to use the series topology as that might be better for his speaker design. In the series topology the x-over components provide a very controlled impedance at each node that can be upset if an external entity (like a speaker cable or a power amplifier - tube or ss) is suddenly introduced into the network. In such a case it would ruin the speaker response.
am i making any sense? Or am i talking thru my hat here?
welcome Mitch2. glad that i could be of assistance in this matter.

I think the reason bi-wiring from a single amplifier causes so much discussion is that it is sort of a poor man's bi-amping .......
Mitch2
oh boy! I really hope that you are wrong in thinking this when you wrote it! IMO it would be a bad hallucination to think that bi-wiring would give you any of the benefits of bi-amping.
I see bi-wiring as a method of impedance control between the speaker & the amp: the woofer driver & x-over see the low impedance of the power amp (assuming the negligible impact of the speaker cable) immediately which helps to control the woofer back EMF. This is in comparison to 1 pair of binding posts where the woofer sees the low output impedance of the amp thru the metal jumpers or short jumper cables + the speaker cable which is worse.
In contrast bi-amping not only has 2 or more amps to drive the speaker but also the freedom to play around with the x-over frequencies & the x-over slopes.
ANyway, hopefully people are a lot wiser now to not mistake the benefits of one for the other. Thanks.
geez!! you said it with a straight-face that i did not get the joke. Sorry! ;-)