I've gotten so many conflcting opinions on the right speaker wire gauge for my 5.1HT system from Radio Shack, etc.

Are there different recommendations for gauges for front, side, center or rear speakers? Is the right gauge also a product of the wire length?

Thanks to anyone who has a good handle on this.

Dorten, the answer to your last question is: "Yes."

Just as in power wiring, the wire size (gauge) is determined by the desire to lose as little power as possible in the conductor, so maximum power is delivered to the load. The power not delivered to the load heats the conductor due to IR2 (current x resistance squared) losses, also known as voltage drop.

However, as with most things, there is a point beyond which the additional gain (actually, less loss) is no longer worth the additional cost. This is known as diminishing returns.

The length of the conductors (round trip distance) is one component used to determine the conductor size. The electrical current of the load is another. The longer the run, and/or the higher the power desired is another.

General consensus is that, because the distance to the rears is (usually) greater than the fronts, but the loudness of the fronts is (usually) greater, you may as well settle on the same size wire for all channels.

But, what size? For typical smaller rooms, with less than 100W/channel, an 18 ga. or 16 ga. wire should be sufficient. Anything larger and/or more powerful, I'd go to 14 ga. or 12 ga. (Note: higher gauge number refers to a smaller conductor)

My system, for example, has the mains (L & R front) powered by a stereo amp rated at 300W/ch., and the center, sides, and rears powered by a 5-channel amp rated at 200W/ch. My amps are below my center speaker, with about 3 ft. of wire to the center, about 6 ft. to the mains, and about 24 ft. to the sides and rears.

I use a high-quality "ordinary" rope-layed (limp) speaker wire of 12 ga. all around. I consider that size a satisfactory compromise between pereformance and cost. I guess the answer to your first question would be: "Not really."

Larry
www.fineelectricco.com

Indeed, and actually I bet most home theatres could get by with 14 gauge. When you start getting into whole house audio distribution where your runs get to be over 100' the 12 gauge would come in handy. Even then some could argue the necessity of such a heavy gauge of wire, but there are other factors such as damping factor that will result in muddy bass response if you go too light of a gauge.

Thanks for your responses! Terrific info which I will put to use.
One other question which you might help me with. I have a Hitachi 53" HDTV and my concern is the placement of my center speaker. It is an Infinity weighing approx. 8 lbs. The only place I have to place it is on top of the the TV. Is that OK? Although it is "shielded" will it interfere with the picture? Will the weight eventually affect the structure stability of the TV?

Thanks again for your help.

Dorten, place the center speaker on the TV. If the shielding is inadequate, the picture would be noticeable. Besides, the magnetic field of the speaker would have to be near the CRTs themselves, not the image, which is merely reflected light. Therefore, it's almost impossible for a rear projector to be affected by a speaker magnet. The weight is negligible.

Larry
www.fineelectricco.com

Larry : don't you mean I2R (current squared * resistance)

Well, yes, I suppose that's what I mean. (Oh, good grief, Charlie Brown!)

Larry
www.dineelectricco.com