Sound Quality Vs. Measurements

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Credible measurements are of almost no interest of the audience, there is not enough space for speculations.

And worse, Pavel, they might show discrepancies of a scope beyond their acceptance capabilities.

Others will reject them because they might ruin their claims of hearing whatever which is not substantiated by measurements.

The loonies live on both sides of the specturm. Their only common ground is that they are all wanna-bes.
 
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At the levels these measurements are made, minus 70 dB or less, it is just differences in shielding being seen. And what a heck of a noise, or is that supposed to be the signal. Sorry, but this is the typical pseudoscience always being used in instances like this. Just because an AP is a fine measurement instrument, doesn't mean that all measurements made with an AP are fine too.

Very busy at the moment. But all the ignorance being sprayed about is not surprising.

First is the issue of connectors, they do not all mate the same and assuming you do not have ones with an iron content which can create easily measurable distortion, they do make a difference. This is well know for cell phone engineers, musicians who have had to tap on a microphone and pretty much anyone who uses low level connectors. Silver used to be the plating of choice as silver oxide actually conducts better than silver. However as many have found you also get sulfur contamination and that does cause silver contact problems. Gold when plated thick enough and correctly to eliminate base metal issues is the better method.

It is not hard to measure connector issues and that reversing a cable with connectors changes the measured results at the -130 db level re .01 volt.

Now for pro audio where the levels are higher contact issues are much less of an issue.

Next is the connection method used to connect the wire to the connector. Some swear by special solders. I have been unable to measure any significant difference here. However a bad solder joint clearly causes problems.

Next is the dielectric. These do not have anything to do with directivity and all of these issues can be dealt with by using a driven shield.

The issue of wire quality and Scott's favorite issue of micro diodes I also find little support for. Measuring a copper strip and then heating it to form an oxide layer did not change the measurements.

The other real issue is how the shield is constructed. If it does not keep out EMI there will be noticeable degradation of some equipment. Equipment that isn't very good to begin with probably won't show any effect, other gear has less difficulty with EMI. So what works for someone may not for another.

Now when I first started off to test to see if there were changes in performance due to the type of solder, finding cable directivity was quite a surprise. Took me a bit over a year of getting consistent results before I showed it to colleagues who watching the results confirmed what I was seeing.

Now since then I have had others either report similar results or steer me to military uses where these kinds of issues are important. Yes there really are applications where they find cables are directional. These almost always boil down to construction issues with the complete cable system.

Now on my list of things to do is to come up with a nice simple method to demonstrate these issues. A bit more in line with how to measure resistors and capacitors.

There is a reason I avoid this thread.
 
vacuphile said:
Has anybody taken the time to read it?
I read it. It contains nothing of any interest to audio. It merely shows that the conductivity of copper wire can depend (slightly) on the details of wire drawing, as this affects the orientation of the crystals. Nothing about signal transfer 'directivity' or 'micro diodes' etc. Just some good engineering, based on the science known at the time.
 
I read it. It contains nothing of any interest to audio. It merely shows that the conductivity of copper wire can depend (slightly) on the details of wire drawing, as this affects the orientation of the crystals. Nothing about signal transfer 'directivity' or 'micro diodes' etc. Just some good engineering, based on the science known at the time.

Dave, completely in agreement, and for those genuinely interested in the stuff cables are made of, still an interesting read after almost 80 years.
 
As for going back in time, I would suggest to let them rant. Otala and Lohstroh have proved their point beyond any reasonable doubt, which they of course will always have, but will not make that amp and listen to it themselves. God forbid, it might actually sound damn good, despite its by now antiquated measuring results, and this would thwart many an "objectivist" jihadist.

No going back in time necessary, Bob Cordell's response was contemporaneous and pretty well thought out. No surprise you have no interest in his conclusions. Your comments are as polarized as those you criticize. BTW there never was any reference to sound, performance, etc. just an engineering look at cause and effect reasoning.
 
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Saw Scott posted in a similar vein. This brings me to the article on copper drawing Scott posted earlier. Has anybody taken the time to read it? Are the science hackers able to find anything even remotely relevant to audio?

Its a good read and some interesting results, how different would the measurements be with todays processes both in copper production and wire drawing would be interesting.
 
Interesting that we've moved into cable thrashing territory, :). I have only a tiny interest in such matters, and that is only in the sense that aspects of the construction and positioning can be an influence - I can easily go from totally obnoxious quality, to fully convincing reproduction without worrying about any of this, so it's well down on my list of "worries" ...
 
I don't know how many degrees we have to get, or how many successful projects that we have been in charge of, to get any 'credibility' with you 'hear no difference' people, but there is no end to the criticism that we get from producing a result different from your initial beliefs. That is why Ed or I can't make a test that you will recognize as useful or even accurate. Now, the 'hear no difference' types are going backward in time to discredit Otala, Walt Jung and me, as well as anyone else who has spent half a lifetime listening to audio differences.

Sign of the times?

The Death Of Expertise
 
diyAudio Senior Member
Joined 2002
Hi,

If Someone like Bruno Putzeys would make a similar measurement, that would put some weight to it.

Similar measurements and others going well beyond this have been done before.
It does not prove much other than that it exists.
What should be proven is the audibility of the results.

I strongly suspect that what John is reporting as audible differences in silver/copper wires has to do with how the wire is cooled down after drawing. (AKA "tempering")
This has an impact on grain growth, grain size, orientation and number of hillocks/voids in conductors.
The process can be further manipulated but that would lead us too far for the moment.

The effect of it has been shown using SEM technique where you can observe electron movement as it migrates across the conductor.
What I'd like to see as well is whether this also increases electrical noise levels and if so by how much etc.

These kinds of studies are mainly oriented towards the semi-conductor industry.
Interest in audio application(s) is extremely low key in general but I do know that some of the better known (audio/video) cable manufacturers in Europe
consult the research results.

Cheers, ;)
 
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Interest in audio application(s) is extremely low key in general but I do know that some of the better known (audio/video) cable manufacturers in Europe
consult the research results.

Cheers, ;)

In my experience research physicists and scientists operating at the highest level (orders of magnitude beyond any audio signals) don't. Why not ask Eric Magnin who instruments the LHC for his opinion? He writes audio related articles.
 
Similar measurements and others going well beyond this have been done before.
It does not prove much other than that it exists.
What should be proven is the audibility of the results.
For what purpose? If one takes the Importance of Everything seriously, and goes to the effort of learning how to discern the subtle differences that occur when something is varied, then I'm sure that valid results will result. And so what? As far as I'm concerned the exercise should be to learn how to achieve high quality audio with the least "fussiness", the bare minimum of performance in all areas that guarantees acceptability of the system, subjectively.

My own experiments indicate that very "mediocre" equipment can get key elements of the sound 'right' if enough fiddling is done, so taking the law of diminishing returns into account should figure very strongly in all this "adventuring" ...
 
diyAudio Senior Member
Joined 2002
Hi,

Why not ask Eric Magnin who instruments the LHC for his opinion? He writes audio related articles.

Thanks, Scott. I may do that.
I talked to the person conducting the research projects at the local university department before.
According to him there is a relation but that still leaves me without any actual proof....

For what purpose?

Because it is extremely important and it's a field I find very fascinating (even though I'm far from an expert).

Going by the feedback I receive from listeners I see correlations with what researchers try to achieve.
Even if the research is more orientated towards far more specialized applications, common factors for success are surprisingly similar.

Cheers, ;)
 
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