What is "biwiring"?


HI. Quick question-what is biwiring for speakers with 2 sets of terminals? I see that some cable companies are using a single strand of wire, terminated twice on the speaker end. Others have 2 sets of wire run together, 1 set each has connectors on the speaker end, but only 1 set total of connectors on the amp end. Another method is using 2 sets of cables-one set having spades on the amp end, one set bananas on the amp, so that both can be connected simultaneously to the same terminal.

Which is considered "biwiring"? Which sounds best?
chiho
Newbee: "Plamenz, Your amps would have to have the same input sensitivity to function properly."

Well, sort of. The input sensitivity has to be the same for the same power output. Some reviewers (but virtually no manufacturers) test and publish input sensitivity for 1-Watt output, and high-power amps tend to have less voltage gain. If one looks only at published sensitivities at rated outputs, 2 amps could be different but the same. They're different in that one is rated 0.5 volts in for 50 Watts out while the 2nd is rated 2 volts in for 200 Watts out. They're the same in that they both have the SAME voltage gain--which means they'll have the SAME output voltages--for the same input, until, of course, the 50-Watter runs out of power.

If the 25-Watter is a receiver, it has volume controls so it sort of doesn't matter what its input sensitivity is, simply adjust the volume to have the treble balance you want.

Personally, this sounds like an exercise in futility to me, as the 25W. amp probably won't SOUND any better than the 70W. amp, and you'll be introducing the impurities of another pair of interconnects to the treble, but it won't cost you anything.

Good luck.
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Thanks, this is helpfull - I think for now I will use the 302 for multi room purposes.
This is probably a stupid question, but here goes anyway. I have a set of B&W CM4 speakers, and a center CMC speaker. They all have 2 sets of terminals; my dealer did not explain anything to me about "bi-wiring," he just said that "true audiophiles" (?!?) just use the lower terminals... From what I have read here, though, it would appear that my speakers are set up for bi-wiring - is this correct? (Told you it was a stupid question, but I'm just trying to learn here!):-o My receiver is not set up for bi-wiring, but I reckon I can just use one terminal for 2 cables...

And, could anyone clarify whether or not bi-wiring makes a sonic improvement? Newbee said he didn't feel there was a meaningful difference, while Bgrazman said he thought it could make a pretty big difference. I realize it all depends on ones own ears and system, but I am curious, and would like to know if its worth the expense to experiment with this.

Also, if you use two cables to each speaker instead of the special - and expensive - biwire cable, I assume that both cables have to be the same brand and type. Just checking; please let me know if this is not so!
Hi Oakiris:
- Fm yr description, yr spkrs allow bi-wiring
- Yr receiver should work fine with two sets of wires connected, as you note.
- Running separate wires to each driver (biwiring) does make a difference -- which differences, when/if beneficial, are NOT commensurate with the financial outlay, IMO. Designer cables are expensive! Instead try hooking up the single cable to the top and then the bottom on yr centre spkr and check for preferred sound. If this isn't indicative, try the same on the main spkrs.
- No, they don't. If they aren't the same, the smaller gauge will go to the top (tweet/mid if applicable) and the thicker wire to the bottom spkr connector (typically the woof). If you're really bent on trying it out, look for some 18-22 g premium copper, insulated magnet wire and use that on top, keeping yr present wires for the lower spkr connection. Keep all wire lengths identical and take care not to short the connections! Cheers
"I have a set of B&W CM4 speakers and a center CMC speaker. They all have 2 sets of terminals; my dealer did not explain anything to me about "bi-wiring," [SIC] he just said that "true audiophiles" (?!?) just use the lower terminals..."

Sounds to me as if your dealer wouldn't know a true audiophile if one walked in the door. It's a cinch the dealer isn't one.

"From what I have read here, though, it would appear that my speakers are set up for bi-wiring [SIC] - is this correct?"

Yes. One pair of terminals drives the lower-frequency part of the crossover*; the other drives the high-frequency part of the crossover.

"My receiver is not set up for bi-wiring [SIC]..."

Amplifiers never are; they don't have the crossovers networks in them.

"..., but I reckon I can just use one terminal for 2 cables.:

Yes, one terminal pair.

"And, could anyone clarify whether or not bi-wiring makes a sonic improvement? Newbee said he didn't feel there was a meaningful difference, while Bgrazman said he thought it could make a pretty big difference. I realize it all depends on ones own ears and system, but I am curious, and would like to know if its worth the expense to experiment with this."

OF COURSE it's worth experimenting with it...or so many of us believe. (Do remember, Oak, that opinions about sound, music, and audio are like as......; everybody's got one and most of them stink. :-) ) Read Audioquest's blurb about it, here http://www.audioquest.com/ . ENTER, Cable Theory, page 5/10. Remove the jumpers between the 2 input-terminal pairs when biwiring.

"Also, if you use two cables to each speaker instead of the special - and expensive - biwire cable, I assume that both cables have to be the same brand and type."

Not so and probably not the best way to do it. Using identical cables gets you only the benefits of separating the 2 magnetic fields. (Read the AQ blurb.) Using different conductor sizes and/or different materials can gain you other audible benefits...and cost you a lot of money, too, maybe... READ more of this subject before playing much with biwiring.

* A 2-way speaker combines bass and mid frequencies in one driver and crossover section, while the 3 octaves of treble are handled by the tweeter. A 3-way speaker divides the frequencies, GENERALLY, with the bottom 3-4 octaves going to the woofer (and this is the lower part of the crossover), 2-3 octaves to the midrange, and 3 octaves to the tweeter. Most biwirable 3-ways combine the latter 2 sections and drive them with one pair of terminals and drive the woofer with the other pair of terminals.
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