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Posted By: iwire Speaker Wire Sizing. - 05/10/03 02:57 PM
Reading some of the replies to this post.

Speaker Wire In Wall

I got to thinking about what I always took as marketing more than science.

The use of 14, 12, and even 10 AWG monster cable for speakers.

I have been "house electrician" for over 100 rock, rap, rave etc. shows, and in that time I do not think I ever saw the sound crews using larger than 14 AWG and 16 AWG was not uncommon for runs from amps to drivers (speakers).

The normal situation would be 800 to 1000 watt per channel amps feeding one to four drivers per channel.

They was no problem with bass response with this setup.

So is there any science to back up that I need anything larger than 18 AWG for speakers in a normal house or car audio system or is it just marketing "Bigger is Better"?
Posted By: Hutch Re: Speaker Wire Sizing. - 05/10/03 04:47 PM
I would say that a qualified yes is required to sufficiently sized speaker and audio cables in the domestic environment. I have experience of two cases, both at the hands of professional electricians, where under-sizing caused serious degradation in performance.

First was my uncle’s audio connections between video and hi-fi – he was at the time a long serving industrial maintenance electrician with what used to be English Electric. I supposed being used to connecting equipment with serious power he thought the hair sized patch cord he made up would be more than sufficient for hi-fi – wrong. He was genuinely surprised when I solved his problem with proper sized cables.

The second case concerns my parents’ house and is a constant bone of contention. After a catastrophic house fire, my father had the opportunity to have things rebuilt to suit modern life styles which included making sure there were sufficient sockets in places where hi-fi and TV/video systems would be, without having to use multi adaptors – the installation sparky thought he was nuts. At the same time he specified for speaker cables to be laid to those places around the room to where he knew speakers and surround-sound units would be – he’s quite an audiophile. He even bought the correct cable for the sparky to install! Only later, long after it was too late to rectify, was it found that different, too thin rip-cord had been substituted by someone that thought they knew better. The system is next to useless and cables now adorn the room that should have been hidden behind plaster.

So how small is too small and what constitutes excess I cannot say, maybe some of our audio-techs could comment but that is my personal experience. 18 feels a bit too small for me. I qualified at the beginning of my post “domestic”. Could it be that your professional equipment (you mentioned a 1000W!) puts out so much grunt that a considerably higher voltage on the cables makes up for their small gauge. Domestic equipment would operate in a far more gentile manner and therefore be more susceptible to signal loss, perhaps.


[This message has been edited by Hutch (edited 05-10-2003).]
Posted By: Zapped Re: Speaker Wire Sizing. - 05/10/03 05:23 PM
Well, in sound engineering school (over 10 years ago now), the accepted idea was that an AC current (which is what audio is) travels away from the center of the wire, so a more finely stranded wire (more little wires per conductor run) is better. As far as gauge, cost is usually the biggest restraint. In other words, go with the biggest wire you can budget. I don't run anything smaller than #14 audio speaker wire, and even use #10 audio for my main drivers.

And btw, you won't notice any appreciable difference in quality with a smaller wire until you crank it up considerably, so if you listen at tollerable levels, you will rarely need heavy wire. Remember, a 200 Watt/channel amp rarely if ever sees that output. More likely, it never exceeds even 25 Watts/channel.

In short, don't sweat wire all that much unless you throw alot of parties or like some serious metal. If you are planning to hardwire your systeem speakers, put in whatever you can afford.
Posted By: james S Re: Speaker Wire Sizing. - 05/13/03 05:06 PM
IS THERE SUCH TABLES THAT CONVERT AMERICAN SIZE CABLES INTO WELL ,MM2
Posted By: wa2ise Re: Speaker Wire Sizing. - 05/13/03 07:55 PM
Take a look at http://home.earthlink.net/~rogerr7/wire.htm

It turns out that all that matters for speaker wire is size. Regular romex or similar electrical wire would be fine for speakers. I used 14/3 with ground romex for feeding the two speakers on one wall of the living room from the other end of the room where the stereo lives. Used electrical metal boxes and the usual fittings so if I ever wanted to use it for power instead of speakers I could.
Posted By: Bjarney Re: Speaker Wire Sizing. - 05/13/03 10:23 PM
How does an amplifier control speaker motion? Bone up on amplifier/speaker damping factor. For audio systems and sound quality, this is a significantly greater issue than thermal or “voltage drop” losses that most electrical folks usually deal with. Kilowatt audio amplifiers are a dime-a-dozen compared to earlier days. Commercial sound folks sometimes neglect damping factor—expecting their big amplifiers to automatically “take up the slop” in speaker leads.
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