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Speaker Cables?

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Johan Liebert
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Thread Starter #82
Why do you need 2 different lengths? If you need 8 meters than I guess you gotta go with 8 meters if that has to do anything with speaker placement and room size.

10 AWG will give you a lower impedance which will be the most significant factor I guess.
 

Karu

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#83
To explain the why. Amp is on left side of room left of the left speaker and then I need to route the cable (WAF) up, over and down a double doorway to get to the right hand speaker.
 

Speedskater

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#84
Guys, is there a scientific conclusion on if unequal speaker cables are a no-go? OCD issues aside, shortest and cheapest for me is 1.5 meters for left speaker and 8 meters for the right speaker
Depending on the loudspeakers, I would say that a 5 to 1 ratio is approaching the difference limit. (5 to 1 is about what you have)
 

cjm2077

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#86
I would think it would go by the overall impedance mis-match from side to side rather than relative change. A 1 ft vs 5 ft cable mis-match makes a lot less difference than an 10 ft vs 50 ft one.
 
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#92
Guys, is there a scientific conclusion on if unequal speaker cables are a no-go? OCD issues aside, shortest and cheapest for me is 1.5 meters for left speaker and 8 meters for the right speaker and I can go with either 12AWG or 10AWG. Any (sound impact) reason not to get the shortest length form each?
I’m sure there are people here who could do these calculations in their heads, but I would figure out how much time it takes for the signal to travel through the cable and see if that makes more difference than moving your head 1 mm to one side.
 

SIY

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#93
I’m sure there are people here who could do these calculations in their heads, but I would figure out how much time it takes for the signal to travel through the cable and see if that makes more difference than moving your head 1 mm to one side.
Time isn't the issue (unless you're talking several miles of wire), it's the effect on frequency response for different cable resistances. If the cable resistance is small compared to the speaker's lowest impedance, then it can be neglected.
 

Karu

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#94
Sounds like it will have practically no effect, I can also go 14AWG that I have lying around for the shorter cable to “equalise” things a bit more. Speaker min impedance is 3.4ohms.
 

SIY

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#95
Sounds like it will have practically no effect, I can also go 14AWG that I have lying around for the shorter cable to “equalise” things a bit more. Speaker min impedance is 3.4ohms.
If the "there and back" DCR of the cables is below 100 milliohms, you have nothing to worry about.
 

DonH56

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#98
FYI attached a spreadsheet (Excel, in zip file) showing the voltage loss and amplitude variation for various cables assuming a perfect amplifier (ideal voltage source). User inputs are in green boxes for cable length, nominal power, and speaker impedance nominal, minimum, and maximum values. Note power is used to calculate voltage loss just for fun but has no bearing on the relative amplitude at the speaker terminals (drops out of the equations). The spread in dB tells how much the SPL might vary at different impedances, which might occur at high or low frequencies and thus change the speaker's frequency response. This is the main reason IMO speaker cable lengths at home might matter; nothing to do with propagation delay, it is about changing the frequency response. Low resistance matters more with low-impedance speakers and ones with low impedance dips, natch. You could also use this to compare two different lengths (or gauges) of wire to the same speaker.

Not responsible for typos/mistakes in the equations -- I am more into Mathcad, Matlab, etc. than spreadsheets for this sort of thing but wanted to us a program most people might have on hand. If you find an error, please let me know and I'll fix it if I can.

HTH - Don

Examples:

10' cables to nom 8-ohm speaker with 4-ohm min and 16-ohm max
1590251053486.png


20' cables to 4-ohm speakers with 1.5-ohm min, 12-ohm max:
1590251153350.png
 

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Wes

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#99
To explain the why. Amp is on left side of room left of the left speaker and then I need to route the cable (WAF) up, over and down a double doorway to get to the right hand speaker.
Will looking at the cable run reduce your subjective listening enjoyment?

Can we convince you to get active speakers?
 

Karu

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Will looking at the cable run reduce your subjective listening enjoyment?

Can we convince you to get active speakers?
Which of the cables? If you mean the left one, it would mean a useless 7-8m spool behind the speaker, which I’d rather not pay for, just collecting dust, and I think there was also some discussion that the spool itself is not ideal signal wise. If the right, going direct on the floor rather than over the door, with a 3-4m cable would leave a thick cable in front of the office entrance to be tipped over on a regular basis. So more practical living related than anything to do with subjective listening.
 

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