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
I don't claim to be any particular expert, but I think biwiring means one connection at the amp end (if the speaker cable is split, you just fasten both together) going to two connections (one high & one low) at the speaker end.

With speakers designed for this, it allows for less impedance mismatching (I think).

It can make a pretty big difference (YMMV) depending on amp & speakers.

happy listening,
Its all bi-wiring, just different ways to skin the kitty. And some folks would suggest that you might be the "kitty". Many manufacturers don't provide for bi-wiring and some that do suggest that its to please customers who believe there is difference. Personally, I have never experienced a meaningful difference, considering the expense. It is fun to play around with different cables to the high and low ends - sort of a way of tuning your speakers high end response to your needs. Just another tweek with enuf supporters to make one curious.
If you use two seperate cables it's called shotgun biwire.
Audioqest calls it single or double biwiring when using a single or a double cable. Most of AQ's speaker cables use multiple conductors of different gage, which make it fairly easy to single-biwire. Their most-common conductor sizes are 16-, 18-, 19-, and 21AWG.

However, many (including AQ) believe one is better off separating the different magnetic fields created by the low-pass and high-pass sections of the crossover by using physically different cables. IOW, they believe you're better off using 2 separate medium-price cables rather than one very expensive single cable no matter how many pairs of conductors it has.

I double biwire my 2- and 3-way speakers. (Virtually all 2-way speaker systems use a high crossover point; most 3-ways use a low crossover point.) The former combine bass and midrange in one section and hence benefit from the 'quality' and 'quantity' parts of the cable, while the tweeter-only section of a 2-way benefits from the very-highest-quality conductors while not needing much material for the low-current treble. Three-ways run bass on the bottom and combine midrange and treble on the top. The bass requires good (but not great) conductor quality but a lot of it. The MR/treble benefits from the very-highest-quality conductors but doesn't need quite the high-current capacity that the bass does.

On my 2-ways, I use AQ's KE-6, a 4-pairs-of-silver, DBS cable, on the bass/MR and KE-4, a 2-pairs-of-silver, DBS cable, on the treble. On my 3-way center, an Aerial CC3B, I use inexpensive Type 6 with 3 pairs on LGC copper on the bass, and KE-6 on the MR/treble.

All 3 of these front-channel speakers have never sounded better.
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In my world, using two separate cables for biwiring is better. I tried the single cable/double pair speaker termination approach. It was clearly not as good as utilizing two pair of cables.

Doesn't matter, spades or bananas. If there's four leads you can double up either one on a termination. With Bananas, you may need a couple plugs like Audioquest's double banana plug, to accomodate all four leads. Then, run one Audioquest double banana into the other.

Budget may decide which way you have to go, though.

If you have the cash, do the job right and run two separate cables, i.e. one for low freq. and one for mid/high.

And, while you're at it, buy another two channel amp, to feed these new wires! ha Now it's getting expensive. But WELL worth it! To achieve truly great results, biwire AND biamp each of your main speakers! I found that the combination of biwiring and biamping Maggie 1.6qr's makes them another creature altogether!

I'm currently using Harmonic Technology cables, and find them to be quite open and detailed, far more so than the Audioquest dbs cables.

Put a serious percentage of your speaker cable dollars to work on the mains. You can always upgrade your sub, satellite cables later.
OK, another question:
Biamping - do the 2 amps must have the same power rating?
For example, I have a NAD T753 receiver (6x70W) and an old NAD (2x25W) - does it make sense to biamp?
Thanks!
Plamenz, Your amps would have to have the same input sensitivity to function properly. If they are different you would have to use a crossover or some form of attenuator for the more sensitive amp. Not as simple as it sounds unless you use identical amps.
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!
"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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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
All good advice, however...

It is a definite advantage to split the signal at the amp end and it is a must to use the same brand cable. Sounds like AQ are talking out of the wrong hole here. For the same reason that you must use the same length you must use the same cable. There is no point matching lengths if the basic electrical properties are all different. The signal getting to the various bits of the crossover must be in-phase and this simply will not happen if the electrons take different routes.

Is biwiring beneficial?
Opinion is divided mainly because the effect can be so different. If you have a relatively resistive wire going to insensitive speakers then the best thing to do would be to give the bass driver as much help as it can get, and go for a single-wire. No point in cossetting the treble if the bass driver is having problems getting its amps. Sensitive speakers don't experience the downside of biwiring nearly as much so its best to get the benefits of keeping the signals apart and go for the biwire option. Shotgunning gives the best of both worlds but then a single-wire configuration of cable twice as expensive becomes an option (an unfortunately good one for many of us).
If you have a relatively resistive wire going to insensitive speakers then the best thing to do would be to give the bass driver as much help as it can get, and go for a single-wire. No point in cossetting the treble if the bass driver is having problems getting its amps. Sensitive speakers don't experience the downside of biwiring nearly as much so its best to get the benefits of keeping the signals apart and go for the biwire option.

Good information, Nullgeodesic. Thank you.

Holly
"It is a definite advantage to split the signal at the amp end and it is a must to use the same brand cable. Sounds like AQ are talking out of the wrong hole here. For the same reason that you must use the same length you must use the same cable. There is no point matching lengths if the basic electrical properties are all different. The signal getting to the various bits of the crossover must be in-phase and this simply will not happen if the electrons take different routes."

Oh my; we're talking about the AUDIBLE differences of billionths of billionths of a second now? '...basic electrical properties are all different'? Hardly.

Audioquest has perhaps hundreds of years of combined experience on its staff of people who care very much about sound quality and how to optimize it thru cable. YOU suddenly are smarter than all of them? I doubt it.
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