I have never experience a difference in speaker volume due to speaker cable uneven length. that is some crazy story.
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Here is the formula from a man who needs no introduction, Sigfried Linkwitz from his Orion site.
I prefer not to recommend any specific product. Cables can have audible effects and some manufacturers make sure they will, either through unusual electrical parameters and/or by suggestion. Weaknesses in the design of the output-to-input interface are exploited. In any case, sounding different does not automatically mean that you now have a more accurate transfer from electrical to acoustical output.
Realize that for an active speaker, such as the ORION, each power amplifier merely sees a voice coil, either of the tweeter, midrange or woofer driver, and that is an easy load. With the lack of passive crossover filter components the speaker cable capacitance and inductance will have insignificant influence upon the voltage across the voice coil over its used frequency band.
My guideline for speaker cables is to keep their resistance to less than 0.1 ohm for the roundtrip path of the current. This defines the maximum length of a 2-conductor copper cable for different wire gauges.
Wire gauge Max. length in feet
I measured the 16 gauge Megacable from Radio Shack (278-1270) that I use. A 10 foot length has 0.07 ohm resistance, 714 pF of capacitance and 1.9 uH of inductance. The line impedance is 51 ohm. A typical tweeter has a voice coil resistance of 4.7 ohm and 50 uH inductance. At 20 kHz this yields an impedance of about |4.7 + j6.3| = 7.9 ohm. Add to this the cable inductance of j0.24 ohm, and 0.07 ohm resistance for 10 feet, and the impedance becomes 8.09 ohm. This causes a 7.9/8.09 = 0.98 or 0.17 dB reduction in tweeter output at 20 kHz, which is insignificant. The cable effect is even less at lower frequencies.
Speaker cables can act as antennas in the AM frequency band and may cause distortion in the output stage of a solid-state amplifier, if strong radio frequency signals are present. In particular, the cable capacitance in conjunction with the inductance of a driver voice coil may form a resonant circuit for these frequencies. The resonance can be suppressed by placing a series R-C circuit of 10 ohm/2 W and 0.33 uF/100 V across the cable terminals at the speaker end.
Coaxial interconnects with phono (RCA) plugs tend to pick up radio frequencies in the FM band. The currents that are induced in the cable shield must not be allowed to enter the inside of the coax. This requires a very low resistance connection between the outer conductor of the phono connector and the chassis (signal ground) of the equipment that it plugs into. The continuity and low resistance of the shield is also very important for hum and buzz currents, so that they will not induce a voltage on the center conductor. The technical description for this is the Transfer Impedance of the cable and connectors, which must be in the low milli-ohm range. Unfortunately I have not seen this specification used by the audio industry. An excellent description of the theory and treatment of hum and buzz problems in equipment setups with mixed two and three prong AC plugs is given in AN-004 by Jensen Transformers, Inc. I have not found balanced interconnections to be necessary for the high level circuits past the preamplifier. But sometimes it requires to experiment with AC outlets in different locations to reduce to insignificant level the buzz that one may hear with the ear close to the speaker cone. So, when choosing a coaxial audio interconnect look for good mechanical construction, direct contact between shield and connector, and well plated contact surfaces.
I find what is needed at Radio Shack. I solder speaker cables to terminal strips on the speaker end and use dual in-line banana plugs on the amplifier end.
Thanks to all who have responded so far; especially Jallen for taking the time to provide a more technical explanation
To Brf: a pair of speaker cable where the left side is 12ft and the right is 7 ft. I am trying to save a few bucks when I upgrade to the next level of speaker cable from the same manufacturer.
If lifting cables off the floor makes a difference, don't you think different lengths might be noticable? Why gamble and wonder what the problem is when your system doesn't seem to sound quite right? Besides, who would buy a set of cables two different lengths when you decide to sell them? I wouldn't.
the left side is 12ft and the right is 7 ft. I am trying to save a few bucks when I upgrade to the next level of speaker cable from the same manufacturer.You'd be loading the amp differently on each channel, as mentioned, albeit slightly in real terms.
However, as wire is inexpensive, my advice is, avoid it.
Gregm wrote:It is a gross exaggeration to say "slightly" in this context. Inconsequential is more appropriate.
Jedinite24 wrote:This is a real consideration, if that is a possibility.
The five foot length difference you referred to, or any other length difference that is likely to occur in a home environment, will result in no perceivable difference in volume. Period.
With respect to possible sonic effects other than on volume, most and probably nearly all speaker cable effects, and relevant speaker cable parameters, are proportional to length. Therefore, if the two cables are identical models but have unequal lengths, their sonic effects can be expected to be similar in character but to be introduced to a lesser degree by the shorter cable.
Personally, I highly doubt that the result of that would be a difference that is perceivable to most listeners in most systems. Even if it were to make a perceivable difference in a given case, however, I see no basis for assuming that the sonics of the equal length situation would be preferable to the sonics of the unequal length situation. Which is the better choice, between the following two alternatives?
(a)Having identical inaccuracies introduced into the sound produced by the two speakers, or
(b)Having less inaccuracy introduced into the sound produced by one of the speakers, at the expense of its sound becoming slightly different than the sound produced by the other speaker?
I don't see any basis for predicting which of those alternatives would be preferable in a given system to a given listener, if in fact it were to make any difference at all (which it probably won't).
Wise men all!! Actually, I had a pair of Analysis Plus Oval 12 soeaker cables about 8 years ago that were a 15ft/8ft.pair. I began to notice about 6 months into use that the one of the channels seemed lower; I don't remember if it was the short or the long run. It seem to get more pronounced over time. Though, I easily sold the cable after an enjoyable 7 years when I upgraded the speakers.
To Markakanetz, Unless you are an old California hippy, I believe you mentioned LSD trips in one of my other threads. For the record, 1972 was my last cosmic voyage.
Augustus Stanley Owsley, the so called "Mad Chemist" died in a tragic car crash last year. He supposedly made 50 million hits of LSD before California deemed it illegal. His brews were supposed to be the best. In his obituary last year in the New York Times, it was reported that John Lennon had contracted with Owlsley to provide him a life time source of his drug. Another useless factoid: Ownsley was reported to have been angered when so one called one of his various concoctions "Purple Haze". He claimed there was nothing hazy, purple, or unclear about his acid.
For the record, "Bear's Picks" a CD of selective Grateful Dead tunes was chosen by Owsley, called "Bear" because he had so much body hair. He also was the genius behind some of of the Dead's sound systems; I think, but am not sure, he may funded and partly designed the infamous "Wall of Sound" which I heard twice driven mostly by McIntosh amps The sound was quite pure and quite loud and could be heard even if you had your head in a wooden box and under your seat at the concert hall. Where did those halycon days go!!!
I'm using a 10' pair (biwired) on my right speaker, and an 8' pair on the left. Sounds better to me than the 10' pair single-wired w/ jumpers. I suppose there's a capacitive difference but I don't hear any downside, or left/right difference.
Ideally, I would have bought another 10' pair, but I found the 8' pair used, so I tried it out, and so far I'm confident the $$ savings isn't clouding my hearing.