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w4rren
2007-03-01, 14:34
I was told many years ago to keep the cable length of each speaker approximately the same. I wouldn’t consider myself obsessive but I like to get the best setup possible for the system I have. Unfortunately I have to put one speaker next to the amp, and the other at the opposite end of patio doors. Can anyone verify if there’s a noticeable sound delay before I slice my speaker wires?

haunyack
2007-03-01, 15:14
I was told many years ago to keep the cable length of each speaker approximately the same. I wouldn’t consider myself obsessive but I like to get the best setup possible for the system I have. Unfortunately I have to put one speaker next to the amp, and the other at the opposite end of patio doors. Can anyone verify if there’s a noticeable sound delay before I slice my speaker wires?


http://www.audioholics.com/techtips/audioprinciples/interconnects/SpeakerCablelength.php

Cheers!

AndyC_772
2007-03-01, 15:16
It's nothing to do with delay - the sound travels a lot faster along the cable than it does from the speakers to your ears.

Keeping the lengths similar is to do with matching levels between left and right. Provided your cable is thick enough not to attenuate the signal significantly, I'd be surprised if you hear much difference. Unless you have a perfectly symmetrical listening room, I'm sure there will be greater differences between L and R than are due to any mismatch in speaker cables.

Phil Leigh
2007-03-01, 15:20
I was told many years ago to keep the cable length of each speaker approximately the same. I wouldn’t consider myself obsessive but I like to get the best setup possible for the system I have. Unfortunately I have to put one speaker next to the amp, and the other at the opposite end of patio doors. Can anyone verify if there’s a noticeable sound delay before I slice my speaker wires?

Fortunately the signal travels at the speed of light which is pretty darn quick so no there won't be a delay that any living creature could detect...unless you listening room is VERY large...

also...with decent cable there's not going to be any noticeable difference in level with a few feet of difference...

w4rren
2007-03-01, 15:43
thanks all, i will start cutting

maggior
2007-03-02, 08:35
I was told many years ago to keep the cable length of each speaker approximately the same. I wouldn’t consider myself obsessive but I like to get the best setup possible for the system I have. Unfortunately I have to put one speaker next to the amp, and the other at the opposite end of patio doors. Can anyone verify if there’s a noticeable sound delay before I slice my speaker wires?

This reminds me of the last time I went to Radio Shack to purchase speaker wire. The man behind the cash register reminded me to cut my speaker wire to identical lengths for each speaker. I immediately thought to myself "huh!?!?!?". So I asked him why (playing dumb). He replied in a very serious and condescending tone "because of the speed of sound, you don't want to introduce delays in one speaker". My jaw dropped. Was this guy pulling my leg? I bit my tongue and decided not to engage him in a discussion about how electromagnetic energy travels at the speed of light and NOT the speed of sound. :-).

ModelCitizen
2007-03-02, 08:45
I've just dug out one of my NAIM (www.naim-audio.com) manuals which clearly states that the cables should be of the same length and under 3m long. They should also be made by NAIM. :-/
MC

cliveb
2007-03-02, 08:54
I've just dug out one of my NAIM (www.naim-audio.com) manuals which clearly states that the cables should be of the same length and under 3m long. They should also be made by NAIM. :-/
MC
Surely that should be *over* 3m long? Naim power amps rely on the inductance of the cable to prevent them going unstable. (Either that, or Naim would like to sell more speaker cable :-)

TimothyB
2007-03-02, 11:00
thanks all, i will start cutting

Likely you've already given your cables a vasectomy, but why not just coil one up behind the amp? That's what I did.

-- Timothy

(who on repainting the living room is likely to put in that funky baseboard that can hide the speaker wires)

SuperQ
2007-03-02, 11:34
Likely you've already given your cables a vasectomy, but why not just coil one up behind the amp? That's what I did.

-- Timothy

(who on repainting the living room is likely to put in that funky baseboard that can hide the speaker wires)

just as long as you don't coil it around a ferrous rod. You don't want any more inductors in the circuit. :-D

ModelCitizen
2007-03-02, 13:07
Surely that should be *over* 3m long?
Yup, you're right... which is odd... as NAIM excel at selling you yet more bits... so it's surprising to see them miss a trick with speaker cable.
MC

Ron Olsen
2007-03-02, 16:07
The main issues with speaker wire:

1. Wire diameter. For short runs, 16 gauge is fine. For longer runs, 14 or 12 gauge is better.

2. Keep the wire lengths as short as possible to minimize resistance in the wire path.

AntiCables states that the distortion caused by the dielectric effect of speaker wire gets worse with increased length, but with their wires, you can run different lengths since they have little dielectric (and their wires have low resistance and inductance). See http://www.anticables.com/faq.html#6 for details.

See http://www.roger-russell.com/wire/wire.htm and http://theaudiocritic.com/back_issues/The_Audio_Critic_16_r.pdf for interesting discussions of the factors involved in choosing the right speaker wire.

pfarrell
2007-03-02, 16:18
Ron Olsen wrote:
> 1. Wire diameter. If your wire lengths are 5 feet or less, 16-gauge
> wire is fine; for longer runs, 12 gauge is better.

12 gauge is good for 20 amps.
What speakers need 20 amps? what speakers can even live with 20 amps of
current?

Unless my arithmetic is faulty, driving a 8 ohm load, you need to
have 160 volts to generate 20 AMPs, which is 3200 watts.

While some monster amps will provide that much power for a second,
the typical 100 watt amp is only going to provide 2.5 amps.

12 gauge is what a monster amp needs from the wall output (or mains).

Seems likely to be overkill for speaker wires. IMHO.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

jacabo
2007-03-02, 16:50
..... which is why i love coming to these boards!

geek on!

-JAC

peter
2007-03-03, 02:40
jacabo wrote:
> ..... which is why i love coming to these boards!
>
> geek on!
>

Dear forum, how thick should the line level cables be that go to my
active speakers?

Confused,
Peter

Ron Olsen
2007-03-03, 03:54
12 gauge is good for 20 amps.
What speakers need 20 amps? what speakers can even live with 20 amps of
current?


Pat,

The issue is resistance and inductance of the wire run, not current-carrying capacity. Roger Russell states that the resistance of the wire run should be no more than 5% of the nominal speaker impedance to have no audible effect. For an 8-ohm speaker, a 50' run of 16-gauge wire is acceptable. For a 2-ohm speaker, a 12' run of 16-gauge wire is the limit.

See Russell's article (http://www.roger-russell.com/wire/wire.htm) for a table of maximum wire lengths vs. wire gauge and speaker impedance. Using wire of a larger diameter than the minimum size recommended in his table will not improve audible performance, but can increase cost. However, it can be a conservative choice if you ever upgrade to lower-impedance speakers or have an in-the-wall speaker wire installation.

Tests by the Audio Critic (http://theaudiocritic.com/back_issues/The_Audio_Critic_16_r.pdf) found that speaker wire inductance is also an issue, and they recommend keeping the wire runs as short as possible, and to use long speaker wire runs only as a last resort. For short wire runs, they say 16-gauge wire is fine.