Soundlab M1 and Alpha-Core cables
I see this talk about skin effect and wonder what you are talking about? In my electrical engineering schooling, we were taught that "skin effect" only occurs at much higher frequencies than what is present in an audio signal - we're talking MHz and GHz, not KHz. Do y'all have some new physics that you use to explain this? -RW- |
>> Skin effect / impedance related high frequency losses definitely come into play in the audio region. This is well documented and has been known since the 70's. You can find independent measurements and test results all over the place if you look around. Sean << Well, as suggested by Sean, I *did* look around a bit. I still stand by my previous assertion. The losses that were demonstrated were on the order of .02db at 25KHz, and approx. half that value at 10KHz. I challenge ANY human to prove he can hear a .02db loss at ANY frequency. It would appear that skin effect is of no practical consequence at audio frequencies. This is not intended as a slam to Sean, he's a great guy and very well-informed. However, in this case, I feel that the skin effect is grossly mis-represented and of no real effect upon a cable carrying audio frequency signals. Go to this link: http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/skineffect/page2.html to read the following: "For the example chosen, at low frequencies the bulk resistance of the copper wire causes a power loss of around .008dB. At 10kHz the loss rises to .009dB if the internal impedance were absent, and .016dB with the internal impedance taken into account. At 25kHz these values rise to .012dB and .028dB respectively. Hence the change in relative signal level from near-d.c. to 25kHz, with internal effects taken into account is around .020dB." -RW- |
Sean wrote: >> Not to single Eldartford out, but he was of similar belief to you (and many others) on the subject of speaker cable audibility << I never said there wasn't an audible difference between speaker cables. I'm using Goertz MI-2s in my system because they "sound" good to me. I'm postive that there is a difference in the sound of speaker cables. What I *did* say was that "skin" effect was grossly over-rated as a reason for these audible differences. I also realize that the equations used to buttress my argument may not be 100% accurate in a real-world environment. But, those equations are *not* off by an order of magnitude. And they'd have to be off by that much (> .2db) before you even *approached* audibility of skin effect. *Something*, or some things, *do* make an audible difference - skin effect ain't one of 'em. Nice chattin' with ya! -RW- |
