Twisting conductors for higher amperage capacity?


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Old 01-30-13, 12:22 PM
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Twisting conductors for higher amperage capacity?

A few years ago I ran twisted shielded speaker wire through the wall to three speakers above my fireplace. The cable was provided by a friend of mine and it is high-quality audio cable. My concern at the time was that the cable was 4-conductor 22 AWG shielded cable when I should have used at least 18 AWG. So, I decided to twist two conductors together for positive and two together for negative for higher amperage. Is this going to cause a noticeable degradation in audio quality? It sounds good to me, but have wondered to this day whether it could be better. Replacing them is not an option, but am still curious. If it makes a difference, the runs are about 20 feet each (left, right, and center channel) and the speakers are rated at 75W RMS.
 
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Old 01-30-13, 03:36 PM
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Did you strip all the coating and twist the entire length of wires together, then recoat it? If not, you were only sized from the largest wire you had, not the anticipated combination of sizes.
 
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Old 01-30-13, 05:55 PM
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Paralleling the wires do not increase the amperage. A wire will carry whatever current you throw at it no matter what the size. The issue with electrical is that the more current (amps) the hotter the wire will get. I think that you would only notice if you pushed the speakers very hard, you might get some distortion.
 
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Old 01-30-13, 06:32 PM
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Combining the wires like that will work just fine.

As a general rule.....doubling a conductor will drop the size by 3 gauges.

So doubling two # 22 wires would yield the equivalent of a # 19 wire.
 
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Old 01-30-13, 07:15 PM
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Agreed, for speaker/low voltage wiring, this is often done. Some high-end wires are actually intended to be paired like this to reduce crosstalk and impedance.

For smaller speakers like yours and short runs, I'd be surprised if you could discern any audible difference either way.
 
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Old 01-31-13, 04:12 AM
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It's not necessary for speaker cable to be shielded. I would connect it to ground at one end only and cut & tape the other end.

The main benefit of heavier speaker wires is a higher damping factor.
 
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Old 01-31-13, 05:52 AM
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Ok. Sounds like I'm fine then. Regarding the shielding, that is the only cable he had available and at the time shielding sounded like a good thing, but now I realize that it isn't necessary since the signal is already amplified. I'm assuming this cable is intended for line-level signals (pre-amp), hence the small conductor size and the shielding.

Paralleling the wires do not increase the amperage. A wire will carry whatever current you throw at it no matter what the size.
Bad choice of words. I should have said "ampacity".
 
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Old 02-01-13, 04:40 AM
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22/2 w/shield is typically used for line or mic level signals in installations. As you've seen, it works with speakers as well.

75 watts with an 8-ohm speaker will pull a little over three amps, which is well within a 22 awg single wire's ampacity. (How many times do you run the system all the way up?)

Use one cable for hot and the other for cold. Speaker lines don't need to be twisted/paired either. We use THHN in conduit for our larger installations.
 
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Old 02-01-13, 08:26 AM
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Speaker lines don't need to be twisted/paired either.
In some instances parallel speaker wire can pick up radio interference and it can clearly be heard through the speakers. This is worse with small-gauge conductors since the amp can't effectively control the extraneous signal on the wires. Twisting won't hurt and often can help. Thankfully this isn't near the problem it used to be when CB radio was popular. The combination of low-ish frequency AM band transmission + illegal boosting of radio output and you would have a neighbors "breaker 1-9" coming out your speakers.

Your wire is undersized by any audiophile standard but probably won't hurt your sound if the speakers are small with small low-mass woofers.
 
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Old 02-02-13, 05:40 AM
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The only instance I can think of where speakers pick up radio is with powered speakers and a faulty connection or component. In that case it wouldn't matter what kind of cables were used.

Low-impedance (4- or 8-ohm) non-powered speakers like Mossman's cannot pick up radio stations and make them audible. They need an amplifier and, again, a faulty connection or component.

That said, the best-selling audiophile speaker cable manufacturer -- Monster -- makes only parallel speaker cables. Like them or not, they must know something.
 
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Old 02-21-13, 05:03 PM
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With wires that are too thin, distortion will show up with louder passages and passages with more bass. I do not know what this distortion sounds like.

Yes you can parallel two thinner wire to get the equivalent of one thicker wire as described previously for audio. (You may not parallel two wires this way in AC power circuits.)

The longer the wire is, all other things being equal, the more voltage drop occurs causing more distortion.

If you substitute thicker wires for the portions of the run outside the walls (easier to string), namely from the amplifier to the wall and from the wall to the speaker, you will get better performance compared with the existing continuous length of thin wire all the way although not as good as a continuous length of thicker wire all the way.

With 4 ohm speakers there are more losses in the wires compared with 8 ohm speakers.

Wires of the same gauge, length, and material will perform the same for audio purposes regardless of stranded vs. solid, oxygenation, or price.
 
 

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