Soundlab M1 and Alpha-Core cables

>> 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-

Rlwainwright: We've been down that road before several times here. Depending on the test methodology, results vary quite a bit in terms of "skin effect" / inductive reactance. When factored into actual use tests i.e. by combining the electrical characteristics of the cable with the load of a typical loudspeaker, bandwidth is further reduced. As such, taking steps to reduce inductive losses in the cable itself can pay off and does become audible under real world conditions.

The other variable here is that inductive losses & skin effect are also part of the impedance equation. Taking steps to reduce both simultaneously also lowers the nominal impedance of the cable. This improves transient and power response, which also factor into the audiblity equation.

Go back and read some of the various debates here discussing such things. Not to single Eldartford out, but he was of similar belief to you ( and many others ) on the subject of speaker cable audibility. As you may be aware of, Eldartford is also an EE and "probably" based his beliefs on the logical deductions that come with the basic formulas that we are taught. After making a direct comparison in his system between two different types of speaker cables i.e. heavy gauge zip cord and an "esoteric" brand, El publicly stated that he EASILY heard major differences in presentation. He also went so far as to put his money where his mouth is and purchased all new cabling, based on his own first hand auditory experiences.

You'll also find that i've offered to lend speaker cables to others that are VERY vocal proponents of "cables iz cables". The person that was the most vocal on the subject in recent memory ( can't even remember who it was ) refused to even consider performing such a test. This is true even though the testing would be performed within the confines of his own system and it wouldn't cost him a thing. At the same time, they continued to "preach" their message, even though they weren't willing to put their own beliefs to the test.

As such, those that are willing to experiment can end up reaping the sonic benefits, along with the knowledge and experience gained. Those that cling to formulas and "theory" become limited by those constraints, missing out on the potential their system and listening enjoyment may hold for them.

Below is a excerpt from a post i made a week or so ago in a power cord thread. It applies here too. Sean
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"PS... Those laughing about cabling ( speaker, interconnect, power, etc... ) making / not making an electrical and / or audible difference lack actual experience in the field. If they had the actual experience, and therefore the knowledge that comes with it, they would no longer be laughing.

Instead, they would be asking "why" and working on ways to further their limited experience and education on the subject. That is, if they were truly intelligent and truly interested in such things. Graduating from a school and / or having a limited background in one specific area of electronics doesn't make you intelligent and / or "well versed" in all areas of electronics.

Most technological breakthrough's come about because someone couldn't understand how something that wasn't supposed to be happening was happening, hence their taking the time and making the effort to understand how / why the impossible was possible. That is, the "impossible" in terms of the level of theory that they / we understand at the time.

Most of the time, things are going exactly as theory would predict. This is why we can do what we can do with repeatable and predictable results. The problem is that most people don't take all the various parts of theory into consideration. Instead, they try to keep things simple, therefore neglecting several of the more complex variables that enter into any multi-faceted equation. This is why looking at the big picture typically explains what is going on in the little picture.

Unfortunately, even the smallest things, like an atom, are phenomenally complex".

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-

Sorry, i misunderstood the motives / point of your question RW.

If you don't think that "skin effect" comes into play, try finding some cabling that is identical other than the conductor type i.e. solid vs stranded with the same gauge and geometry from the same manufacturer. Since surface areas, dielectrics and grade of conductive materials should be near identical, the only variance would be "skin effect" due to "strand jumping". The biggest difference will be in treble clarity, which is where most of the smearing takes place. Sean
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