ARPRINCE Posted October 13, 2004 Share Posted October 13, 2004 When laying out your wires, I read somewhere (couldn't find the hread anymore) that you need to have the same length for the MAIN FRONT L-C-R speakers and the same length for REAR L-R speakers. True and Why? TIA Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 13, 2004 Share Posted October 13, 2004 My opinion on the center channel is that it can be as long as it needs to be, that is, it need not be the same length as the front L/R cables. The rest of what you said is correct. For clarity, the rear L/R wires should be equal length, and the front L/R wires should be equal length. The respective lengths of the front pair should be as long as they need to be. Same with the rear pairs. There is no correspondance between the front pair and the rear pair as far as wire run is concerned, only between the respective pairs (front OR rear). The more one tries to explain this, the more messy it gets! DM Quote Link to comment Share on other sites More sharing options...
ARPRINCE Posted October 13, 2004 Author Share Posted October 13, 2004 Thanks for clarifying that for me. Quote Link to comment Share on other sites More sharing options...
lynnm Posted October 13, 2004 Share Posted October 13, 2004 Wire length is meaningless so long as the wire used is of a reasonable guage. An electrical impulse travels at about 186,000 miles per second ( ie. The speed of light) so a difference of even a few hundred feet in the length of wiring between an amp and the respective speakers will not effect the timing of the signals' arrival from the amp to the speaker. The level ( ie. amplitude ) of the signal will however be effected by the resistance of the speaker line so when one is running very long lines the use of lower guage ( ie. heavier wire ) is advisable as lower guage wires offer less resistance to current flow than higher guage wires. A couple of points to consider: 1.) As mentioned above electricity travels at about 186,000 miles per second therefore in real terms the time delay occasioned by the signal having to traverse 100'to one speaker as opposed to 1' to the other speaker is of such minute difference as to be calculable but virtually unmeasurable.BTW Let's ignore theories that suggest electrons transmit energy in such a way that there is no actual travel of electrons ( insisting that there is only a transfer of energy and therefore the time delay issue becomes even less relevant). 2.) If in fact there is a time delay resulting from differences from wire length would they be audible ? Hardly ! Given that electricity travels at 186000 miles per second and that sound travels at 1780' per second one would need be several thousand feet away from the speakers to detect the difference in sonic output from the speakers( assuming that the speakers were playing loud enough to be heard from a distance of several miles away ). 3.) The electrical impulse having reached the speakers must travel through the crossovers and the drivers all of which employ much higher guage wire than the speaker cables even if one ere using the smallest legal guage of zip cord. Bottom line use reasonably heavy guage wire for all of your speakers to mitigate the effects of resistance and don't worry overmuch whether the lines are of equal length. Quote Link to comment Share on other sites More sharing options...
marksdad Posted October 14, 2004 Share Posted October 14, 2004 thanks you lynnm, wire length unless different gauge or signifigant length differences means little, wire offers so little resistance, and electricity so fast, that it amounts to nothing Quote Link to comment Share on other sites More sharing options...
WMcD Posted October 15, 2004 Share Posted October 15, 2004 Naturally I agree with the above good advice. The speed of an electical signal in wire is less than than light in a vacuum. Still, the ratio of a signal in wire to sound in air is about 500,000 to 1. At least according to my calculations. So relative delay is nothing to be worried about. There is some concern about "loss" because of the differences in length. Still, this is negligable in living room lengths. = = = = It would be nice in a way if the ratio was not so big. People worry that the mid driver in a K-Horn is 20 inches behind the tweeter. We could solve that by delaying the tweeter with a long run of wire to the tweeter. It would be 20 million inches of wire. Of course we must use gold plated interconnects and very, very thick wire to prevent electrical looses (edit loses). Smile. But of course then both would have be delayed even more to wait for the woofer. Now we're talking lots of wire. Gil Quote Link to comment Share on other sites More sharing options...
lynnm Posted October 15, 2004 Share Posted October 15, 2004 Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted October 15, 2004 Share Posted October 15, 2004 Gil, I always enjoy your calculations! Thanks again, just imagine (or calculate, if you will), how much volume that much xover-tweeter wire would take up inside the speaker enclosure? get your calculators out folks, Gil's working it right now! Michael Quote Link to comment Share on other sites More sharing options...
WMcD Posted October 18, 2004 Share Posted October 18, 2004 Gee, initial calculations are more favorable than I thought. It is only 320 miles of wire. = = = = Edit: I had read "Voices Across the Sea" by A.C. Clarke about the effort to put the first trans Atlantic telegraph cable from Newfoundland to Ireland. It was about 3000 miles of ocean and the sucessful effort (after many failures) used Isamard Kingdom Bunnel's (sp) "Great Atlantic" steamship to do it. I think they had 5000 miles of cable on board. (Some of the numbers didn't quite work out in my head.) This is to say, we're talking about 10 percent of a very big boat load of wire to get tweeter delay. VAtS was reprinted in "How the World Was One". (You see that VAtS is a quip on Hands Across the Sea, lend lease, and HtWWO is a quip on How the West Won. A.C.C.'s wit; not mine.) I do recommend this reading. Sort of a trivia question and answer. The New World and the Old World have been in "digital communication" (Morse Code) with each other since about 1870. Smile, Gil Gil Quote Link to comment Share on other sites More sharing options...
TBrennan Posted October 19, 2004 Share Posted October 19, 2004 Lynn and Gil---Personally I've given up on trying to talk sense to audiophiles. I'm now content to let them believe any cockamamie nonsense that suits 'em. Quote Link to comment Share on other sites More sharing options...
richinlr Posted October 22, 2004 Share Posted October 22, 2004 Only one comment. I don't care about the physics involved (so far all of it posted is correct). Put 30 feet of wire on your left channel and 5 feet of the same wire on your right channel. After doing this, please try to tell me that you did not have to adjust the balance control ever so slightly toward the left to get the image in the middle... Physics is great but we must all be good observers as well... Quote Link to comment Share on other sites More sharing options...
marksdad Posted October 22, 2004 Share Posted October 22, 2004 wow some people can talk themself into anything, i am currently running my left rear at 40' of wire and my right rear at about 25', and there is absoutly no difference in sound. funny huh? Quote Link to comment Share on other sites More sharing options...
psg Posted October 22, 2004 Share Posted October 22, 2004 I don't care about the physics involved (so far all of it posted is correct). Put 30 feet of wire on your left channel and 5 feet of the same wire on your right channel. After doing this, please try to tell me that you did not have to adjust the balance control ever so slightly toward the left to get the image in the middle... Physics is great but we must all be good observers as well... And you're not kidding? You have to touch the balance control for 25 feet of wire? Then replace that 28 AWG and put in some 12 or even 14 AWG. Quote Link to comment Share on other sites More sharing options...
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