Axiom Home Page Forums General Discussion Technical Questions Speaker Wire - Dumb Question

I'm pretty much a newbie and this question may show it. I'm running my speaker wire through my wall, up to the attic, and down the side walls to my QS4's. The runs are 50' & 40'. I've read that I need to use UL listed wire since it's in the walls, but what gauge would you suggest? I was guessing 12GA due to the distance, but would 14GA work since it's only going to be sent to the surrounds? Like I said, it may be a dumb question, but I had to ask!
Any help is GREATLY appreciated!
KOSMOS

I don't doubt that you could get away with 14 ga, but I wouldn't follow the argument that surrounds need lower gauge wires. Since they're farther away, it's more important to have high gauge going to them.

KOSMOS, Ken is spot on and I've got 14 ga running 35 and 40 feet to my QS8s. Not only is the audio superb, I believe the setup is non-life threatening.

I've also got to chant my mantra. There are several sources of wire. You can argue various merits all day long. After years of arduous research and personal consultation with the Pope himself, I bought my 14 ga speaker wire at Home Depot. STo my ears, it sounds just as good as Monster Price wire. Plus, it was something like 20 cents per foot. Go back to the bulk wire and have them cut it to the length you need.

Amen. Can I have a hallelujah?

Thanks for the push in the right direction! I've used Home Depot for my previous wire purchases, just wasn't sure about the gauge!
Thanks again for the help! Can't wait to get it all hooked up!

Kos, Ray is right on target. When I was in Rome His Holiness also advised me that God didn't make no bad copper and that it was sinful to waste money on the high-priced stuff. As Ray said, a good source would be the section in Home Depot where they have the big spools and can cut what you need. As to gauge, it's probably time to cite the speaker wire article again. You'll note from the table that 14ga should be plenty for your needs.

Are you suggesting that the Pope's grammar is going downhill along with his health?

Have they rehabilitated Galileo yet? Shades of Giordano Bruno!

Peter, I know what I heard. I trust my ears.

You're amazing.

Time to make myself some enemies on this one...

I'm of the "wire is wire is wire" camp - except with one caveat - gauge.

Consulting a nomograph - you should be looking at about 10ga. wire for your run.

For a:
RL (load resistance) of 8 ohms
40ft run of 2 conductor copper
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14ga. will give you a damping factor (RL DIV RS) of 40 which is low for home theatre (but fine for performance arena).
10ga. will give you a damping factor of 100.

What is damping factor? Here's what Marantz has to say about it.

Having said that... the driver size of the QS4s and their duty in the HT setup mean they don't need to be as responsive as your mains, but this is something to consider.

Bren R.

In reply to:

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Consulting a nomograph - you should be looking at about 10ga. wire for your run.

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Yes, but 10 gauge wire is awfully thick and hard to pull through walls. Best of both worlds would then be 12 gauge, right? I think the 14 would still be adequate for most of us.

Damping factor can be significant in system performance, but sometimes is over-emphasized. Some time ago sushi pointed out the falsity of the claim of "tighter bass" supposedly provided by some solid state amps with very high damping factors. I concurred and referenced speaker designer Dick Pierce's findings on the point. That article now appears in expanded form here in Audioholics. Note the insignificant effect on damping at bass resonance shown in the first table until damping factor is in the low single digits. The separate matter of response fluctuations due to speaker impedance fluctuations is shown in the second table(columns 3 and 4 reversed)and is of more significance than damping at bass resonance, but wouldn't appear to be of audible significance at the frequency points involved until at least a damping factor under 20.

The conclusion is that Mr. Russell's suggestion of speaker wire resistance of not more than 5% of nominal speaker impedance(i.e. equivalent to a damping factor of 20 if receiver output impedance was zero)is reasonable and allows sufficient damping factor when combined with typical solid state amps having output impedance of less than 0.1 ohm. Of course in some worst-case situations involving high amp output impedances of several ohms(e.g. many tube amps), that in itself is sufficient to cause audible inaccuracies.

For runs of about 30 feet to my QS8s, I initially used Carol 12-ga. UL wire. It was probably overkill, but was only $19.30 per 100 feet. There were no problems with flexibility or routing. http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=100-740 I planned on running the cable in-wall, but just tacked it around the baseboard since I had other changes planned. Later when the room was recarpeted I used Radio Shack 14-ga flat under carpet wires. It worked great, can't feel it under the carpet, and no detectible sound difference from the 12-ga wire. http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F010%5F006%5F000&product%5Fid=278%2D1273

10 gauge speaker wire is multi stranded and not the same as 10 gauge electrical wire which is very difficult to pull through walls.

I back up Bren on the wire gauge - just think of the electrons as water through a pipe. The bigger the pipe the better the flow. The longer the run, the more your signal attenuates (weakens) and if you start with a small gauge wire, it may reduce your sound quality or put an extra load on your amp.

In reply to:

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I back up Bren on the wire gauge - just think of the electrons as water through a pipe. The bigger the pipe the better the flow. The longer the run, the more your signal attenuates (weakens) and if you start with a small gauge wire, it may reduce your sound quality or put an extra load on your amp.

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Umm... I'm glad you agree with me... but I didn't necessarily make any of those points. Again, the mantra is inductance, capacitance and resistance.

I appreciate JohnK's link to the explanation of the practical effects of damping factor... I've been hoisted by my own petard, I guess the more correct wording should have been "less than optimal" rather than "low" in my original message.

Bren R.

I had no idea what a petard was, until just now when I looked it up. Here's a pic:



It's an explosive used to destroy walls. How does the saying "hoisted by my own petard" make any sense?

The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.

petard

SYLLABICATION: pe·tard

NOUN: 1. A small bell-shaped bomb used to breach a gate or wall. 2. A loud firecracker.

ETYMOLOGY: French pétard, from Old French, from peter, to break wind, from pet, a breaking of wind, from Latin pditum, from neuter past participle of pdere, to break wind. See pezd- in Appendix I.

WORD HISTORY: The French used pétard, “a loud discharge of intestinal gas,” for a kind of infernal engine for blasting through the gates of a city. “To be hoist by one's own petard,” a now proverbial phrase apparently originating with Shakespeare's Hamlet (around 1604) not long after the word entered English (around 1598), means “to blow oneself up with one's own bomb, be undone by one's own devices.” The French noun pet, “fart,” developed regularly from the Latin noun pditum, from the Indo-European root *pezd–, “fart.”

Ah, thanks for the clarification. Makes much more sense to me now. I though it had something to do with a flagpole.

Well, If you were sitting on a flagpole and there was “a loud discharge of intestinal gas,” and you fell off the flagpole you would be "hoist by your own petard."

It was either the Franks or Turks who started using explosives in sieges... and since fuses back then were "15 seconds give or take 20 seconds"... many a sapper was "hoisted by his own petard".

Bren R.

Getting back on topic, what gauge wire would one use to make a 1000' run between a petard (pile of dynamite) and an electronic detonation device?

A thousand feet, Peter? You really want to make sure that you're not hoist by your own petard. But, to detonate electric blasting caps the lead wire is typically an insulated 20 gauge single strand copper wire. There are a few dynamitophiles who prefer to use silver wire. Although measuring instruments have indicated that there's no difference in the intensity of the blast, they insist that it sounded louder and of higher quality to them, and that years of listening to dynamite has allowed their ears to develop an exquisite sensitivity.

Once again, baiting for JohnK has paid off handsomely! Thanks for that.

Here's a sidenote about "exquisite sensitivity" and blast noise. A long long time ago I was a television camerman. On Remembrance Day we were covering the local ceremonies which included a salute from a 88 howitzer. I thought that it would be a great idea to get a shot of the gun going off from the viewpoint of the bottom of the barrel. I positioned myself at the right side of the gun and aimed upwards so that you could see the length of the barrel and the muzzle in the shot. When the howitzer went off I was hit by a shockwave so intense, that I could actually feel each of my internal organs. For the first, and to this point, only moment of my life, I was aware of exactly where my liver, stomach, and kidneys were positioned. I don't believe that this experience aided my appreciation of music in any way.

So you were close enough to touch the howitzer when it fired? You are one brave man. But I betcha that footage was priceless.

Had a similar experience in Nam. Charlie would figure where our artillery was and find a location that was unreachable from any of those bases; a safe zone, if you will. To offset this, when we'd discover their location, before daylight, we'd move a bunch of mobile 155s (the biggest at the time were 175s I think, so these were no. 2) 10 or 15 miles to the point where we could reach the bad guys. We'd then proceed to give them a wake up call.

I was a sound man on a motion picture crew filming this particular fire mission. There were more than 10, but less than 20, of the 155s. When they opened up, the earth moved, and I couldn't breathe for a few seconds. I don't think it aided my appreciation of music either.

Thanks Jack. Not to glamorize or romanticize it, but I love hearing war stories. One of my teaching mentors was a vet of Iwo Jima and elsewhere. He was full of good stories.

Apologies for being so far O.T.

Mark,

I am a student of WW II history with particular interest in the Pacific theater. I wish I could have talked with your mentor. Anybody who lived through the battle for Iwo Jima, has earned my profound respect. It was a nightmare.

tinman - your story goes a long way towards explaining the hat you are wearing in your Avatar. You should be glad you can still HEAR music, let alone appreciate it.

BigWill - quick story. My Dad was a Master Sgt. in WWII and was on an island called Tinian. I'm watching JAWS with him several years back. We watch the scene where Quint and Richard Dreyfus compare scars and Quint tells about the Indianapolis going down. Dad has never said much WWII up to that point. He casually says, "I remember watching the Indianapolis depart and someone told us later that it sunk."

Long story short, the Indy took Fat Man & Little Boy (Hiroshima & Nagasaki A-bombs) to Tinian. Super top secret, that's why it took so long to go after the survivors. Anyhow, Dad went on to explain that his squad of MPs supervised the unloading of the bombs. I thought that was pretty neat.

Hey Jack, my buddy moved to Vegas a couple years ago. I called him before Xmas when I heard he wasn't doing well (cancer).
He never made it off the beach at Iwo. Shot in the neck, they had him in the "waiting to die" section when the sgt running the med-evacs off the beach recognized him as a neighbor kid. Made sure they got him out to the hospital ship. Partially paralyzed, but he survived.
He was a fun, old, crusty MF.

Mark,

What a story! I never cease to be chillingly awed by the capriciousness of battle. Wish I'd had a chance to thank him, and thank him, and thank him, for his sacrifice. I hope you did.

Tinfoilhat:

I'm still not sure what drives shooters to get "that shot"... bro's the camera op in the family. I stick to the graphic/animation and audio side - corrective lenses and eyecups don't mix... doesn't help that he's built like a tripod and I'm more a monopod (both 6' 3", I'm 155lbs, he's somewhere over 200)... we were working the Military Tattoo here one year, him on the arena floor with the shooty bits, me up in the booth... he set up a great shot just before a fusillade... and got a quick and painful reminder that rifles eject to the right... sonuvabee got 5 hot brass rounds that dropped into various parts of his tech vest - but never gave up the shot.

Bren R.

You are right about photogs getting the shot above all else. When the howitzer went off I thought for a moment that I might actually be dead, but the footage showed only the slightest nudge that lasted just 2 frames and then the camera stabilized. I was shooting handheld at the time. Man, you do stupid things when you're young.

Ajax,
if you're a big study of WW2 you should attempt to locate the documentary series "the Valour and the Horror". It was developed for CBC and was something like 20hours. They focused mostly on Canucks role in the war. Extremely graphic and very haunting. Probably one of the best documentaries I've ever watched on WW2 - and should be required viewing for any person, Canadian or otherwise.

Thanks Scott. It sounds very interesting. I'll see if I can find it. Thanks again.