Ben Hanson wrote:

Sorry if this double-posts, I couldn't tell if it went through on my news
server or not.

Hi all, I heard someone mention the other day that if you wanted to get
some
good speaker cable, that you could save money and still get good quality by
just going to the local hardware store and buying some 12/2 electrical
cable
(or better), cutting the ends off, and putting on the connector of your
choice.

12 gauge is fine for most normal 6-8 ohm loads. You do want to keep it
away from electrical wires. If you must cross them, do it at 90 degrees
or keep the parallel distance to less than a foot or two.

You can also use a roll of 12 gauge electrical wire, though you'll
have to gently place the ends in a vise and a drill motor and wind
them together. 1 full turn per foot is fine. Heat shrink tubing works
well to keep this from unravelling. Zip ties work as well.

I am setting up some Community speakers that require amplification and I
wanted to make up my own cables with Speakon connectors. Could I really
just
go up to Home Depot or Lowe's and buy 100' of 12/2 or 10/2 cabling and make
my own, or should I buy cables specifically made for audio? Is there really
a difference?

All commercial installs that I know of use heavy gauge wire, preferably
run in its own conduit or seperately. Speaker wire isn't rated for
pulling with AC, though, while electrical wire is. The compromise
is to run it with the cable TV/phone/low voltage stuff.

For that "slick" look, terminate the wires at a 1/4 inch wall
jack and use a fancy looking 1-3 ft gold plated patch cord.

Also, I am assuming the conductors need to be twisted strand, not solid
core, if you were going to use this approach? And lastly, if you can only
find 12/3 cabling, is that a problem? Can you just not use the ground wire
and leave it alone on both ends of the cable?

Really, it makes no difference. Heavy gauge Romex or heavy gauge coax
also will work, though they are a PITA to work with compared to
stranded. IME, 10 or 12 gauge heavy coax is the most stable as it
can be run almost anywhere, even outdoors, but it's incredibly hard
to work with.

One thing - you do need to calculate the signal loss for the run.

http://home.earthlink.net/~rogerr7/wire.htm

IMO, 5% loss is too high. Aim for 2%. For the impedance,
figure out the lowest impedance for the speakers.
This should be ~5-6 ohms for most 8 ohm speakers.

Roger lists 5%, so 2% effectively means 40% of the length
shows on that chart.(ie - use the 16 gauge row). With a
6 ohm load, 50 ft requires about 10 gauge. 4-5 ohm, 8 gauge.

If you are running very long runs, you may need to go to 10 or even
larger gauge. If you get below 10, think about coax as an alternative.

IIRC, someone had a calculator that would spit out exact values,
but I can't find the URL.