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Wire Length Calculator

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NoxMorbis

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Nobody who knows buys CCA. It's pure copper that is desired.
Sure,. but I have a 20 foot run to make on my right side. The room is split by an entry way. I'm going to try and get it on the other side, but where I sit, I won;t be directly inbetween the speakers. If it weren't for that 20 foot one way run (40 feet out and back), it would only be like 8' one way.
 
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NoxMorbis

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I'm an outlier:

My speakers go below 2 ohms up high.

My speaker wire is 2AWG THHN since I had it, and the terminals, and both the speakers and amplifiers can accept it.

For no reason other than I could (and did). It all came from my scrap box.

They're not flexible, and there's no need for them to be.

index.php


Those are 1/2 inch (13mm) nuts for scale.
LOL, nice. might as well use solid core.
 
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I'm not having any luck finding what I think is a proper wire gauge calculator for amp to speaker runs. Some say "enter length" but they don't specify if the 'length' is one way or x2 for both ways, to and from the speaker, and CCA vs Copper drops. (Although the price between the two is really negligible for my usage and I'll most likely use copper in order to use smaller gauge wire.

Any links?

PS--I did this a couple of years ago, but I actually did it the hard way by getting the resistance of the wire and speakers and calculating it that way. But I've forgotten if I should use x2 the one way run length and I'm too lazy to look up the specifics of my wire resistance etc. lol
You should use x2.

Go with the Benchmark Excel sheet. It's as far as I can see based on sound formulas.

Also you should consider what gauge is sold most. Most hardware stores have rolls of wire and it could be cheaper buying smaller gauge and running double/parallel.
 
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NoxMorbis

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You should use x2.

Go with the Benchmark Excel sheet. It's as far as I can see based on sound formulas.

Also you should consider what gauge is sold most. Most hardware stores have rolls of wire and it could be cheaper buying smaller gauge and running double/parallel.
Checked Home Depot today and their wire is not out of sight. it's actually cheaper on Amazon. Their 16 AWG lamp cord use to be really cheap, like 25 cents a foot.. Now they want 70 cents a foot for it. I can get copper 16/2 marine wire on Amazon 100' for 25 bucks. From what I have read, a 16 AWG copper wire for 40 feet (total length or 20' each way) or less is more than adequate for 4 or 8 ohm. The decibel loss would be under 0.4dB for 8 Ohms and .8 dB for 4 Ohms, generally. Unless I'm missing something, at least according to this Audioholics chart. The chart is for 8 Ohms so /2 for 4 Ohms, but still, unless I'm missing something, 16 Gauge is fine. I mean I can't hear (for 4 Ohms) 0.8 dB difference on a one way 20' run using 16 guage:

AudioHolicSpeakerWire.png
 
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Checked Home Depot today and their wire is not out of sight. it's actually cheaper on Amazon. Their 16 AWG lamp cord use to be really cheap, like 25 cents a foot.. Now they want 70 cents a foot for it. I can get copper 16/2 marine wire on Amazon 100' for 25 bucks. From what I have read, a 16 AWG copper wire for 40 feet (total length) or less is more than adequate for 4 or 8 ohm. The decibel loss would be under 0.4dB for 8 Ohms and .8 dB for 4 Ohms, generally.
Yeah, prices are bananas!

So relieved I don't have a house to renovate in these times..
 

Martinvb

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I'm an outlier:

My speakers go below 2 ohms up high.

My speaker wire is 2AWG THHN since I had it, and the terminals, and both the speakers and amplifiers can accept it.

For no reason other than I could (and did). It all came from my scrap box.

They're not flexible, and there's no need for them to be.

index.php


Those are 1/2 inch (13mm) nuts for scale.
Aren’t you afraid that you may cause a shortage with this type of binding?
 

Blumlein 88

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Aren’t you afraid that you may cause a shortage with this type of binding?
With his amps the fear would be melting everything down if there is a short. It does appear his connections are rather sturdy.
 

fpitas

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Most peeps here are using 12G for long or short runs. It really fits well in both of those parameters. Try amazon for good prices.
And Monoprice
 

fpitas

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A note about using the various wire charts: if you have a modern amp with tremendous damping factor, the wire resistance will degrade the DF. If you care, you must take that into account.
 
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NoxMorbis

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A note about using the various wire charts: if you have a modern amp with tremendous damping factor, the wire resistance will degrade the DF. If you care, you must take that into account.
Did Russel have this wrong, then, or how should his chart for runs be interpreted?

1681592462950.png
 

fpitas

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Did Russel have this wrong, then, or how should his chart for runs be interpreted?

View attachment 279513
His chart is fine for most purposes. But if you own one of those amps (Benchmark AHB2, NCORE, Purifi etc) with high DF, and are a believer in extreme DF, it will be best to increase the wire gauge. See the Benchmark link in post #6, for example.
 

pjug

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Did Russel have this wrong, then, or how should his chart for runs be interpreted?

View attachment 279513
He says his maximum length is "based on the resistance of the speaker wire not exceeding 5% of the rated impedance of the system", so not a very tough threshold. That is why the max lengths are so long. I guess any threshold you choose is somewhat arbitrary, but I think most here wouldn't want more than a couple/few tenths of a dB deviation in frequency response because of wire resistance. If you plug the maximum values in that table into the Benchmark spreadsheet you will get more deviation than that for most speakers.

Another problem with the above table is that max and min speaker resistance matters too, not just nominal.
 

RayDunzl

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Aren’t you afraid that you may cause a shortage with this type of binding?

I keep an insulator jammed vertically between the leads.

It's a Home Depot wooden paint stir stick.

1681559300808.png
 

Chrispy

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A note about using the various wire charts: if you have a modern amp with tremendous damping factor, the wire resistance will degrade the DF. If you care, you must take that into account.
How does that particularly matter, tho?
 
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NoxMorbis

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He says his maximum length is "based on the resistance of the speaker wire not exceeding 5% of the rated impedance of the system", so not a very tough threshold. That is why the max lengths are so long. I guess any threshold you choose is somewhat arbitrary, but I think most here wouldn't want more than a couple/few tenths of a dB deviation in frequency response because of wire resistance. If you plug the maximum values in that table into the Benchmark spreadsheet you will get more deviation than that for most speakers.

Another problem with the above table is that max and min speaker resistance matters too, not just nominal.
Oh F-it! That's why I have decided to go with this! Then I'm going to solder it directly to the speaker terminal outs and the amplifier posts. Yeah!?

614XNssak6L._SL1000_.jpg


Seriously, though, did he do that because he knows you won't hear any difference?
 
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Chrispy

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Oh F-it! That's why I have decided to go with this! Then I'm going to solder it directly to the speaker terminal outs and the amplifier posts. Yeah!?

614XNssak6L._SL1000_.jpg


Seriously, though, did he do that because he knows you won't hear any difference?
Maybe because of different applications somewhat. Cars usually need lower impedance setup.
 
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