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BillyB
04-10-2007, 05:57 PM
This question may seem trivial but I must ask it.I have Tara Lab solid core prism bi-wire feeding my Quad 22L's.I moved one of the speakers for better imaging and the wire was fed from below and wasn't long enough so I had to splice it.I wasn't thrilled with this as the speaker wire wasn't cheap and being a purist I always worry if stuff like this can truly deteriorate performance.Just looking for some feedback because I can resolve this issue with some work.If It's worthy I can open up the ceiling below and re-route the wire and eliminate the need for the splice.I am a home remodeler so the repair for me isn't tragic.Thanks and sorry if this question sounds stupid.

Luvin Da Blues
04-10-2007, 06:02 PM
I too fret about anything I think I can reasonably improve. If only for piece of mind I would re-route it...removes any doubt now or in the future.

Mr Peabody
04-10-2007, 06:35 PM
Each splice is said to add resistance. If left and right wires are different lengths there is supposed to be timing issues. If you use the same kind of wire before and after the splice I think you'd have to have some sensitive ears to hear the difference. If you used some other wire to extend the Tara I'd bet there is a noticeable difference.

BillyB
04-11-2007, 02:18 PM
Each splice is said to add resistance. If left and right wires are different lengths there is supposed to be timing issues. If you use the same kind of wire before and after the splice I think you'd have to have some sensitive ears to hear the difference. If you used some other wire to extend the Tara I'd bet there is a noticeable difference.

I did use the same Tara cable to extend it but it has made the cable run longer than the other channel.I've heard the argument for keeping the speaker cables as close to the same length as possible.This is making me lean towards re-routing the wire for peace of mind.Thanks for the reply.

Mr Peabody
04-11-2007, 04:37 PM
I know what you mean, I was trying to be objective. I personally wouldn't have spliced but my best technical reason, other than what I already stated, is I lean toward the obsessive compulsive edge.

mlsstl
04-11-2007, 05:42 PM
I'm not sure I buy into timing considerations when considering typical home speaker wire lengths. I ran through some "back of the cocktail napkin" math. Light travels at 186,000 miles/sec in a vacuum. There seems to be some variable in how fast electricity travels in a wire, but just for the sake of the example, I used one-third the speed of light. That works out to 330 million feet per second in wire. An extra 10 feet of cable (20' on one speaker and 10' on the other) would add 0.00000003 seconds in travel time. Even at 20KHz (which has a wavelength of about 0.056') the phase shift between the channels would be on the order of 0.06% or about 0.2 degrees. The phase shift would be half that at 10KHz, and even less as the frequency goes lower.

Since sound travels at roughly 1000 ft/sec in air, an extra 10' in cable is the audio equivalent in phase shift at 20KHz to moving your head in the listening position about two-thirds of an inch away from the "ideal" position. I know I try to sit still when doing critical listening, but I don't think I'm buying a head-vice anytime soon!

I would say changes in other parameters - resistance and capacitance for example, would be more important differentials with unequal speaker wire distances. While I don't claim the above math as peer reviewed, I think it gives a reasonably valid impression of the correlation between speaker wire length differentials and phase/timing issues.

Dusty Chalk
04-11-2007, 07:40 PM
I think the piece of mind is worth the rerouting. Remember: if you believe it will have a deleterious effect on the sound, that worry will ruin the sound more than the splice, so remove the cause of the worry.