We commonly get asked about what kind of speaker cable should I use, or speaker wire, for my home theater or stereo system? And the short answer is "use the heaviest-gauge cable that you can afford and that you can get away with if you have space limitations or you have super, super long runs of cable."
Compare a heavy-gauge cable, like a 12-gauge cable, to a 24-gauge cable. The heavier-gauge cable has a lower resistance. What that means is that you get a better transfer of power from your amplifier to your loudspeaker.
Why Is Power Transfer Important?
If the transfer isn't optimum - and it wouldn't be with a long run of this thin little cable - you're actually going to lose some of your amplifier power in the cable. And there is no need for that. That just doesn't make any sense. You're throwing away available power to your speaker just because you haven't used a good quality heavy-gauge speaker cable.
One other problem is that if you use a very thin-gauge cable, you can actually start modifying the sound of the speaker. People don't realize this, but if the resistance of that wire is high enough, it now acts as another crossover component that's in series with the loudspeaker and can actually cause you to lose bass performance.
So What Gauge Speaker Wire Should I Buy?
What we recommend is if you're going to be using runs that are less than 20 feet, anything 16-gauge and heavier is appropriate. And that's a lower number, so 16, 14, 12-gauge, is a good idea.
If you're going to be doing runs that are longer than 20 feet, I always recommend you should use 12-gauge cable. The longer the run, the more resistance.
If you're going to be running through ceilings and walls and things like that, use the heaviest-gauge cable that you can. You'll be getting every watt of that amplifier power you paid for to the speaker.