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Old 3rd November 2008, 04:25 PM   #10121
syn08 is offline syn08  Canada
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Quote:
Originally posted by PMA
Syn08, you are not any original even in your posts here. Your argueing in Post #10117 is completely copied from the Audio Critic magazine, and that article is not interesting at all. There is no qualified critique in it.
:bs: Do you need me to spell it for you?

David Rich holds a PhD in EE, so he's more than qualified to talk about. Between his rationale and your biased opinion, guess who is more credible.
 
Old 3rd November 2008, 06:21 PM   #10122
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What we have here is a conflict between two belief systems: The hear-a-difference people and the near-no-difference people. I'm in the hear-a-difference camp, so I will side with Dr. Hawksford, until PROVEN otherwise. I want to try to explain the differences in cable, rather than presume that it is all nonsense. It does me little, or no good, to dismiss EVERYTHING unless it is peer approved.
 
Old 3rd November 2008, 06:51 PM   #10123
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A false dichotomy. I never got the impression that Dr. Hawksford was promoting himself as a spokesperson for one side or the other. In fact I rarely ever see his actual listening experiences in print, though I have not sought them out. Usually you hate his kind of carrying on, tedious analysis, simulations, complicated measurements on even more complicated circuits. The cable result as pictured in his paper is not very interesting. A suddenly stopped sine wave into a simple RL would also show a tail as would a tone burst into any real speaker (orders of magnitude more delayed energy in this case). It has been shown may times that some exotic cables and some speakers have easily heard (by some) 10ths of a dB response anomalies, no one argues that they can't hear them.

There is not much difference here to the person that measures -112dB vs. -109dB seventh on a preamp and says "there end of story, that must be what I hear".
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Old 3rd November 2008, 06:56 PM   #10124
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Quote:
Originally posted by john curl
What we have here is a conflict between two belief systems: The hear-a-difference people and the near-no-difference people.
You are correct. For all the hear-a-difference people, here's an amazing deal: a magic brick for $55!!!!

http://www.audiogon.com/cgi-bin/cls....-5-Magic-Brick

Don't miss this opportunity to significantly improve your system!!!
 
Old 3rd November 2008, 07:02 PM   #10125
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Intolerance.
 
Old 3rd November 2008, 07:05 PM   #10126
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Quote:
Originally posted by PMA
Intolerance.
yes, to :bs:
 
Old 3rd November 2008, 07:24 PM   #10127
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Gents,
Around 1984 I talked with my audio Guru who told me of a discovery he had made. The said that for audio, cables carrying signal must be 1/ solid core and 2. as thin as earthly possible.

This of course made no sense to me but I was enoughh to try out these theories, and went home and replaced my speaker cables with 28 gauge wire wrap wire, one strand per terminal. What a wonderous revelation!

I then made interconnects from 40 gauge enamelled copper wire with similar improvements - to my ears.

These ideas were shared with many others in the Sydney (Australia) hi-end scene with universal acceptance by those open minded enough to actually try.

Then in 1985/6 Prof hawksford came out with the essex Echo papers in HiFI News and RR givingtechnical explanations for what we had been hearing for over a year.

IN the 90's I wrote a book called "The SuperCables CookBook, where I reprinted the Prof's orginal article, as well as a simplied version for non mathmaticians - for which the prof gave me an "A".

Since then we have commercially made cables using ultra thin wire and foil, the foil of course being able to be as wide as needed to get the resistance down, as www cannot be expected to drive big woofers!

I am a fan of the Prof's work, and from over 20 years of testing and commercail manufacuring, I stand by his theories, as do my clients. I don't care what counter theories maybe advanced, cables made to his theories work better than any other we have tested.

Regards, Allen (Vacuum State GmbH)
 
Old 3rd November 2008, 07:28 PM   #10128
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Quote:
Originally posted by scott wurcer
My personal opinion is that the case for skin effect and audio is highly overstated. Hawksford's study for one has been discredited by at least one person whose expertise is more suited to the problem. Mathematical results at this level of sophistication are easily misinterpreted.
Hi Scott

I find it strange that nobody ever pointed out the fact that his experiment used steel wire, not copper. JC stated years ago that the steel had a mu of approximately 100.

The internal inductance of a cylindrical wire is 15 nH per foot (oops, 15nH per foot time mu), so the wire MH tested had 30 times 100 nH per foot, 3 uH per foot.

Squeezing the conductors together certainly reduces the external dipole field, but as long as they are round, there will be that nasty 3 uH per foot term. Truncating the sine will certainly cause issues with that inductance.


Quote:
Originally posted by john curl
I had heard of different conductivity of various offerings of copper due to purity or annealing, but I had no real understanding of it at first.
Appearently it is easy to bring out these differences, that seem so subtle at room temperature, at very low temperatures. Then, different copper samples can measure quite differently from what would be expected at room temperature.

Well, super cooling a piece of copper or any other metal does much the same thing. Once you remove the fundamental resistance mechanism, you are left with a 'residual'. It is the 'residual' that I would like to address in future comments, and what contributes to it.
Hey John, long time no talk. I hope all is well with you.

Absolutely...the relevant parameter is called RRR, or residual resistivity ratio. It is a parameter of the metal that defines what it will do at low temperatures. For superconducting magnets, it's an important parameter for the superconductor stability prior to a quench, and defines the thermal and electrical conductivity of the metal in the presence of a magnetic flux, usually in Teslas.

Typically, it's really just a relation between the mean free path in the structure vs temperature.

Here a few links to the information:

http://cryogenics.nist.gov/MPropsMAY...Copper_rev.htm

http://accelconf.web.cern.ch/accelco...C1989_0506.PDF

The interconnect you mentioned, would you happen to know it's characteristic impedance? Did anybody ever measure L and C?
Cheers, John
 
Old 3rd November 2008, 07:35 PM   #10129
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>A "Shakti Stone" type tweak for many, many dollars less.<
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Old 3rd November 2008, 07:37 PM   #10130
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I returned to hifi audio, as a hobby, some 7 years ago, after 20 years gap (20 years ago I built something and believed it was beyond audibility limits ), first only as a hobby, then it became a small part of my design, consulting and business activity.

6 years ago I would swear that cables make no difference, impossible, nothing to measure, nothing to hear.

5 years ago I would swear opamps are the best audio solution.

3 years ago I had quarrels with John here (my apology).

During those 6-7 years, my view at audio has completely developed and changed. Without continuous listening experience and comparisons, my view would have been the same as 7 years ago.
 

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