Choosing audio cable thickness

[Artas1984]

The best audio cables have low resistance - the shorter and thicker the cable is, the lower the resistance is.

But would i actually feel the difference switching from a 0,8 mm diameter cable to a twice thicker?

According to the "Maximum wire lengths for two conductor copper wire" rule, my cable length and width fit the 8 ohms load of my speakers without any penalty, however the thicker cables surely would improve resistance, therefore what better values would come out from it and how would i feel the difference?

[sanlyn]

Unless you're rigging something like 400 feet of speaker wire, the average home speaker setup would be less a matter of "resistance" and more a matter of spectral impedance (the relationship of inductance and capacitance with wire type and length). Thinner wire has less high-frequency modulation but more low-frequency modulation, thicker wire has better bass and, depending on thickness and very high inductance, less efficient for high frequencies. 18g to 16g speaker wire should be sufficient, provided it's designed for loudspeaker use with proper inductance/capacitance values. You'll also get less "noise" or "fuzz" and more clarity with solid-core rather than stranded-core wire (and that eliminates lamp cord and most of the junk wire sold at BestBuy and Radio Shack). Silver-plated copper tends to sound harsh.

If you really want to get into some thick discussion on various speaker wire, try a look at Stereophile or The Absolute Sound reviews.

OTOH there's a school of thought that says all wire sounds alike. If that's the case, it doesn't matter. Use whatever you have lying around.

[jagabo]

how would i feel the difference?

You won't.

But since you'll know which wire you're using you'll convince yourself via the placebo effect that one sounds better than the other.

<edit>
Well, you might notice a difference if the cable run is very long. Say, 100+ feet. Mostly what you'll notice is the thicker cable is a little louder. Keep in mind that when blind testing is performed almost everybody will say the louder audio "sounds" better, even if everything else is the same.
</edit>

[sanlyn]

The O.P. states that 0.8mm wire is used, which equates to about 20AWG solid-core wire. I'd go for 18 AWG solid-core. Many can tell the difference between stranded-core and solid-core in clarity (and many can't hear any difference, period, so there ya go). The so-called golden eared audiophiles claim they can tell blindfolded which of 4 or 5 similar speakers in the same room is working, but only with source material that they've heard at least a few times, and they say they can tell if cables have been switched. Be that as it may, if I'm familiar with the source I can distinguish between solid-core and stranded-core speaker wire of similar AWG, but only in the treble.

And for what it's worth, a local golden ear insists that "quality" speaker wire and interconnects from the UK sound "cleaner" that U.S. products. I remain skeptical, although it's a fact that different cultures prefer a different overall tonal balance; In Japan they like a somewhat cold sound with marked treble, Americans tend to perk up with bloated bass and strident treble, and Europeans tend to like a smoother concert hall effect. This isn't just myth: if you listen to an orchestra play a piece in Lincoln Center and then listen to the same performance in Carnegie Hall, they don't sound the same (the former being notorious for wiry treble. It's true. I've heard it myself. And acoustic engineers haven't been able to fix it). I'm with jagabo here, you're not likely to hear a difference with thicker wire unless you're talking about long speaker lines, in which case thicker wires would have a less effortless quality with cleaner treble and maybe more solid bass = and that's assuming that what you use now isn't junk wire with tin connections, as cheap wire tends to have a boxy sound because of uneven impedance at various frequencies, the tendency to develop striations and internal cracks, and whatnot.

Of course there's one way to find out. Try it and listen.

[Cornucopia]

If you've got a larger living room, and you're doing a surround sound system, that means that, with nicely dressed cables (straight, right angles, "hidden" wires), you could have >40-50ft runs on the surrounds. Since you don't want your surrounds to be "weaker" than your mains, it makes sense to use somewhat thicker cable. I use 12g "zip cord" (often used for indoor 2-wire power lines), but you could probably get by with 14g, maybe 16g without the HF losses in the surrounds not being noticeable in an A/B comparison. I would NOT use 18 or 20 or certainly higher AWG, because at those lengths it can be possible to hear the difference (depending of course on your own acuity).

Scott

[Artas1984]

If you've got a larger living room, and you're doing a surround sound system, that means that, with nicely dressed cables (straight, right angles, "hidden" wires), you could have >40-50ft runs on the surrounds. Since you don't want your surrounds to be "weaker" than your mains, it makes sense to use somewhat thicker cable. I use 12g "zip cord" (often used for indoor 2-wire power lines), but you could probably get by with 14g, maybe 16g without the HF losses in the surrounds not being noticeable in an A/B comparison. I would NOT use 18 or 20 or certainly higher AWG, because at those lengths it can be possible to hear the difference (depending of course on your own acuity).

Scott

That!

This is what i am going to do.
For the front and center speakers i will leave the 0,8 mm diameter cables, since the length of those will be short, but for the rear speakers, which will be behind my back, i will connect them with 1,4 mm diameter cables, since they will be considerably longer. This way i will be able achieve the same impedance with different cables.

http://www.ampbooks.com/home/amplifier-calculators/wire-inductance/

Example: a 1,5 meter long, 0,8 mm wide cable will have an impedance of ~ 50 miliOhms, same as a 4 meter long, 1,4 mm wide cable. 50 miliOhms is just 0,625 % of speaker impedance, so that is great. I have read that it should not exceed 5 %.

What happens when wire impedance reaches over 5 % of total system impedance?

[Cornucopia]

You get undesirable changes in freq. response (mostly high-end rolloff) and phase-response (some freq. delayed relative to other freq., and not necessarily linearly).

IIWY, I'd keep ALL my cables the same thicker size.

Scott

[Hoser Rob]

All those properties like inductance and capacitance may matter in cables that have to pass radio frequency. Not audio. It's just BS. There were a number of very good articles ... I actually have one by Chris Russell of Bryston ... written around 25 years ago by serious engineers/designers (not poser critics/PR hacks in disguise) on the subject.

However, their dealers ... who make a lot of money accessorizing you with those silly cables ... screamed so loud that they stopped writing them.

Basically, whatever of those properties a speaker cable has is so absolutely dwarfed by those present in the speakers themselves, they don't matter. Even if the crossover parts are all 1% tolerance it's extremely unlikely the cable impedance will throw it off spec.

The resistance does matter though. It's a long standing engineering rule of thumb that when you have a current source driving a load like a speaker, the output impedance (R) of the input shouldn't exceed 5% of the speaker resistance. That includes the resistance of the speaker wires plus the amp's output R, which you can figure out from the damping factor.

Of course, this all depends on how long the cables are. There's tons of info on this stuff on the web.

Will you 'feel' it more with larger wire? Depends on what you mean by that. Many people would mean bass. Actually, since thinner wire = less damped bass, you may actually feel it less with heavier wire. Depending on what you mean of course.

[sanlyn]

All those properties like inductance and capacitance may matter in cables that have to pass radio frequency. Not audio. It's just BS.

Wow. You are dead wrong. To the point of not realizing that weirdo capacitance and inductance glitches can blow up an amplifier. Literature on this goes back 100 years. The 5% rule still applies, though.

[Constant Gardener]

It's worth having thicker insulation on speaker wires. Our 16 gauge wires have survived decades of rampaging vacuum cleaners and pouncing cats.

[Artas1984]

You get undesirable changes in freq. response (mostly high-end rolloff) and phase-response (some freq. delayed relative to other freq., and not necessarily linearly).

IIWY, I'd keep ALL my cables the same thicker size.

Scott

Now you are contraindicating yourself? What kind of help is this? You are just confusing the mater, not helping...
Whatever..

[Cornucopia]

No I'm not! Thicker is better - period. Use as thick as you want (or as is practible). If you go thinner, you start to get freq. & phase problems which get worse the longer your cables are. Thinner the cable, shorter the length before those problems start being manifested.

>40-50ft? Don't use 18G or higher. For consistency, I've got all my cables being thick, including the shorter ones (though that's clearly not necessary). Works better for correctly dampened bass and doesn't provide unexpected impedance mismatches with the amp.
*Note: I have a custom 9.1 system, so I need to have things exacting. YMMV. (particularly depending upon your hearing - but this is my JOB).

Scott