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what is bi-wiring?
#2445 04/04/02 11:18 PM
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Is this as simple as twisting two wires together and plugging it into one slot? I will have 4-16 running through the house for ambient music in the bedrooms (small 30-50W speakers or so), but from what I'm reading 16ga isn't good enough for the home theater. If it is this simple, what's the guage equivelant of two 16s?

If it helps, I'm consider the M3Ti's+VP150 for the front.

Thanks!

Re: what is bi-wiring?
#2446 04/07/02 09:49 PM
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Biwiring is the process of feeding the different sections of the speaker crossover with separate cables (feeds) from the SAME amplifier channel. So your initial assessment of connecting the wires at the amp by twisting them together is about correct. You must observe polarities, and your speakers must support this.

The benefits are somewhat vague, with different opinions from those on each side of the arguement. As for the wire and guage requirements, the cable needs to be of sufficient size to not limit the output levels. A serious factor that comes into play is distance from speaker to amplifier.

Re: what is bi-wiring?
#2447 04/08/02 10:03 PM
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So to bi-wire, the speakers must support this. I'm guessing bi-wiring is a 2-wire output to a 4-wire input.

Distance from amp to speakers would be about 30'. It's a new construction, and I haven't yet decided if the components will go in the basement or in the same room as the HT.

Now, what happens if I twist the wires (matching polarity) at both ends, in effect making the 4 wire cable into a 2 wire cable? Would this harm the system? Would this equal a 12ga cable?



Re: what is bi-wiring?
#2448 04/08/02 10:58 PM
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Hello Martian,

When you twist the pairs together, you will lower the resistance, which is always beneficial. You can't harm anything. If you are running 30 feet of cable, I'd use 14-gauge or thicker. But I suspect your twisted 16-gauge pairs would about equal the 14-gauge.

If you really want to get techie, go buy a cheap Radio Shack digital AC/DC volt-ohmmeter and actually measure the resistance. It's fun! So long as you keep the total resistance (both directions) to 0.3 ohm or less, you have no problem. Those little ol' electrons will zip along quite happily at the speed of light, not knowing at all whether they're "bi-wired" or "single-wired"!

Regards,



Alan Lofft,
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Re: what is bi-wiring?
#2449 04/08/02 10:59 PM
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Martian,

I am not sure what you mean. Why would you twist the 4 wires into 2? If you want 12 ga wire, just buy 12 ga wire.

Yes, the speaker must support this. If you look at the back of a speaker, you'll see the binding posts. If there are 2, it's not to be bi-wired. If there are 4, then you can bi-wire it. So, yes, two wires leave your amp, and 4 wires enter the speaker.

I think everyone would agree you should keep the components, especially the amp, as close to the speakers as possible. It is always best to keep wire lengths shorter.

Re: what is bi-wiring?
#2450 04/09/02 04:37 AM
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Martian, I believe that you're unduly concerned about this, due to reading something about 16 ga not being "good enough" for home theater. Such a statement is nonsense; home theater usage makes no difference in speaker wire requirements. The determining factors are still the length of the run and the impedance of the speakers. As Alan points out, in your usage speaker wire resistance of 0.3 ohms or less would be fine. A 30 foot run of standard 16 ga lamp cord would have a resistance of about 0.24 ohms. Neither 12 ga nor doubled 16 ga is necessary. The only audible effect the lower resistance would be a miniscule increase in volume at the same amplifier setting. The same result would be accomplished by turning the volume control a tiny bit higher. Relax.

Re: what is bi-wiring?
#2451 04/09/02 04:22 PM
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Thanks for the replies everyone!

I will have lots of wire left over from the spool of 4 conductor wire, so this is why I was asking whether I should combine the wires to "increase" the guage for the home theatre portion instead of buying even more cable. However, it doesn't sound like it will be necessary in my case. I guess if it came down to it, I could "double wire" the speakers since there'll be two wires just sitting there anyway.





Re: what is bi-wiring?
#2452 04/09/02 05:36 PM
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Martian

yes, you could use one wire for the positive, one wire for the negative. I have done a simple test with that. I had one speaker double wired and another single wired, and there was a difference, but only on wire that was very thin (22 ga).
With 16 ga wire, I don't know if doubling it up will make a difference. The best way to find out is to try!

let us know how it turns out!

Re: what is bi-wiring?
#2453 04/10/02 11:39 PM
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No you would not harm the amplifier. You would simply increase the composite size (gauge), and decrease the composite resistance.

Speakers must be designed for providing multiple sections of the crossover to be separated. The main use is for bi-amping which is driving the different speaker drivers with separate amplifiers. Some people have used this to provide the same channel amplifier output to the different speaker drivers using wire separated at the speaker binding posts, and connected together at the amplifier - biwiring.

There is a theory behind this design, but the speakers definitely must be designed with a method of separating the crossover sections.


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