Al, 0.15uH/ft seems high. Inductance of gauge 14 straight copper wire is about 0.036uH/ft. For silver it would be slightly less. Twist of two wires would lower it further.
Long Speaker Cables/Short Interconnect or reverse
I'm considering re cabling my system and have a question regarding the desirability of using of long speaker cables with a short interconnect, as opposed to shorter speaker cables with a long interconnect. I currently run a 21 foot pair of speaker cables from my equipment stand to my speakers, and a one meter interconnect between my pre and power amp. I could move my power amp closer to the speakers which would allow me to use a 11 to 12 foot pair of speaker cables, however would necessitate about a 11 foot interconnect. My preamp is an Audible Illusions L3 which does not use a cathode follower and has a relatively high (1.2Kohm) output impedance, however they claim a longer interconnect can be incorporated as long as it is of a low capacitance type. It is a single ended pre so a balanced interconnect is not possible. So is it advantageous to cut the speaker cable length by 10 feet or so if the interconnect is lengthened by 2+ meters? My speakers are specified as 8 ohm nominal, 6 ohm minimum (I read a post by the technically well versed Almarg who stated that allowable cable length is dependent on speaker impedance), and my amp is solid state with an input impedance of 50K ohms. Although logistically trickier, I could also possibly move both the preamp and power amp closer to the speakers, and run the longer interconnect from my cd player (RA Opus 21 with an output impedance of a low 100 ohms) which would need to physically stay where it is
Thanks in advance for all your advice...
Thanks in advance for all your advice...
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- 13 posts total
Hi Kijanki, I believe that what I said is correct. According to this wire gauge table the diameter of 14 gauge copper wire is 1.63 mm. Plugging that into this inductance calculator, together with a length of 12 inches, results in an inductance figure for a physically isolated single conductor of 358 nH, or 0.358 uH. Signal Cable Silver Resolution is spec'd as having an inductance of 0.13 uH/foot, presumably reflecting the combined inductance of the two conductors, which are described as having a twisted and "cross-linked" geometry. Clear Day is described as having an inductance of 0.30 uH/foot run. Certainly there are many audiophile-oriented cables having inductances that are way lower than both of those figures. But 0.13 uH/foot, and perhaps even 0.30 uH/foot, would represent low enough impedances at frequencies of interest, at a 21 foot length, to be insignificant in relation to the impedance of Brad's speakers. Even more so considering that the impedance of most dynamic speakers (which I presume are what he has, based on the impedances that were indicated) tends to rise at upper treble frequencies and beyond. Best regards, -- Al |
One of the biggest improvements I've made to my system is eliminating the speaker cables and binding posts entirely. I went to monoblock amps placed very close to the speakers, and ran the internal wire from the speaker crossover directly out to the the amplifier binding posts, eliminating the speaker binding posts. Huge jump in clarity and image focus. My speaker cables were 3m Zu Ibis silver cables, no slouches, but no cables at all sounds much better. So, based on my experience, I'd say that anything you can do to shorten (or even eliminate!) the speaker cables should be beneficial. |
Here's a picture of how my speakers are wired. It's a biwire arrangement, with one wire for the woofers and the other for the mids and tweeters. Wire is Cardas copper litz in teflon, wired directly to the crossovers. Obviously the crossover is in a box external to the speakers. Crossover Direct to Amps The sound is definitely superior to using the Zu Ibis cables with binding posts. |
- 13 posts total