I don't believe cables make a difference, any input?

[SY]

If someone on the other side of twon has a Mc Donalds Hamburger for dinner, whta does this tell me about the taste of my breakfast?

What does T. Lobsang Rampa have to do with an inapt analogy?

then try to understand what they potentially CAN hear.

That's vital.

And since you have the sorts of controlled, blind testing data that can fundamentally affect the way we think about wires, you do us a great disservice by not writing up a JAES paper. I'm serious, not being facetious. You're claiming something very interesting and, if replicable, something potentially profound.

[Peter Daniel]

Originally posted by SY


What does T. Lobsang Rampa have to do with an inapt analogy?

It seems like some of you need to have their third eye opened (like Tuesday Lobsang had) to hear the difference

[ThorstenL]

Konnichiwa,

Originally posted by SY


And since you have the sorts of controlled, blind testing data that can fundamentally affect the way we think about wires,

Do I? I have noted repeatedly that I did the tests for my own use, simply to find out "what works best". To make sure that I did not deceive myself I used blind testing in some (not all) tests.

However, I never as such bothered to test for difference. If you read my comments earlier in this thread you'd find that I already knew that cables made a difference, even though common EE lore says they should not....

At any extent, these tests where not made to publish AES Papers. Actually, about the last thing I'd do is to write AES papers or worse JAES articles. It suffices to me to know WHO and WHAT kind of articles they routinely reject to know not to bother.

LASTLY, if you actually read the JAES you will find published a number of ABX cable tests. The first one showed some positive results despite using already unrealistically low significance values for the size of the dataset generated. The author was severely criticised and as a result re-tested with even lower significance levels, resulting in fewer "false positives".

By the time the tests finally gave the desired answer (Null) the statistics applied had been "adjusted" such that for the size of the dataset "false positives" could be ruled out with great certainty, yet at the same time the risk of obtaining flase "null" results was maximised such that obtaining a "null" result became more than 95% certain....

To note, the tests started out with a for small scale tests realistic criteria of 4/5 as "positive", when the results where positive when "null" was desired the criteria was altered to 9/10, which still threw out too many positives, so it was altered again to 19/20 (or in statistics .05 significance).

This is an excellent example for how there are lies, damned lies and the Ststistics & ABX Tests.

Originally posted by SY


You're claiming something very interesting and, if replicable, something potentially profound.

I am claiming nothing past the following specific points, made earlier:

1) Cables make differences.

2) These differences can be audible, measurable or neither with current technology.

3) Some of these differences may be easy to measure using conventional measurements but are inaudible.

4) Some of these differences may be audible but are not covered by conventional measurements.

5) Many of the differences arise not from the direct (signal transmission) but indirect facors (key factor "pin one problem") in unbalanced interconnections between multiple, mains powered pieces of equipment.

I repeat, instead of arguing about other peoples data, how about you generate some data of your own?

But make sure to calibrate you ABX test by first testing a number of known audible phenomenae to make sure your test as such works and is discriminative enough. Then you take all the glory and write your own JAES article.

Most likely it will be one on how ABX tests with a small sample size and analysis to .05 significance FAIL to reliably detect virtually ANYTHING. You will very likely find that you cannot reliably identify one channel out of phase with other under such condition, or rather, you will find you can but the ststistics will say you didn't.

Enough ABX tests have been published with full data included. If you actually re-analyse these tests with significance levels apropriate to their sample size you will find that the majority of these test must be considered as having actually pointed to an audible difference being present, HOWEVER, the small smaple size makes the risk of "false positives" quite high if you even out the possibilities for type A (false positives) and type B (flase negatives) Errors.

So, contrary to your comments non of my claims are either profound or interesting, instead they are boring and old and enough data exists to support a very reasonable contention with regards to claims that certain tests yielded "null" results and support instead claims that in fact they showed that differences where percieved.

AES papers and JAES articles on the subject exist, though the ABX Mafia and the Anti Cable League has studiously avoided to take note. No point adding another article to what already exists.

Sayonara

[IanHarvey]

Originally posted by Bratislav


Hey! Why stop with engineering now when it gets most interesting ? Get the job done ! Go all the way - plug in some numbers. We know typical L/C values for a speaker cable. We know dimensions/physics (thickness, length, insulation diameter & dellectric constant) of it. We know currents involved. We knwo a typical speaker (terminating) impedance. Let's see some numbers !!!

(f/x: checks physics qualifications. Still working - good).

1. Assume we have two parallel conductors 3mm apart, carrying 1A each (into an 8ohm speaker of typical efficiency, that's a healthy 95dB). The force between two conductors length L spacing R is:
F = mu0 * I * I' * L / (2 * pi * R)

(Google for "force between parallel conductors" for references). Plugging these in, at 1A we get F = 6.6E-5 N per m of cable length.

2. I don't know how springy speaker insulation is, so let's just let our conductors float in free air and use the force to move them back and forth; the maximum amplitude we get is limited by the maximum acceleration the force can produce.

So, assume our conductor has a mass of, say 30g per m; using F = ma, our force can generate a maximum acceleration in the cable of 2.2E-3 m/s^2.

Let's assume our test frequency is 300Hz; the acceleration of the cable is (w^2).D, where D is the peak displacement and w is 2*pi*freq. (Google for "simple harmonic motion" for references).

Plug this in, and get D = 2.2E-3 / (2.pi.300)^2 = 6.3E-10 m.

3. Capacitance between two parallel conductors is complicated, but a fair approximation for a number of geometries is that it's proportional to 1 / distance between conductors. So the fractional change in capacitance between our conductors 3mm apart is:

(1 / (3E-3 - 6.3E-10) - 1 / (3E-3 + 6.3E-10) )

which comes out as 4.2E-7 x the cable's original capacitance.

4. Supposing our cable's initial capacitance was 1nF, and we're looking at the change in impedance presented at, say, 15KHz. The change in capacitance is (4.2E-16) farads, which at 15KHz has an impedance of 2.5E+10 Ohms.

In other words, the effect of 'magnetostriction' on typical audio signals is comparable to putting a 25,000Mohm resistor across your tweeter.

Cheers
IH

[Pjotr]

Post 407:

Originally posted by Kuei Yang Wang


...... Any of the above is fully defendable even in a court of law (or worse - a peer reviewed journal), as a basically true thesis.

Do you agree or disagree? If you disagree, please specify WHY, taking into account ESPECIALLY the way in wich human perception & hearing differs from technical/mechanical measurements of known quanteties....

This something along the line:

My breakfast tasted like Groimpfwszaom this morning. Wow that was a delicious breakfast. You don’t agree? How dare you, if you disagree, please specify WHY, taking into account ESPECIALLY the way in which human perception & tast differs from technical/mechanical measurements of known quantities.

In other words claiming something to be true and it IS true until somebody disproves it? Reverse/upside-down reasoning

Did not read this whole lengthy thread, so maybe it came along already:

http://www.audioholics.com/FAQs/Audioquest.html

[ThorstenL]

Konnichiwa,

Originally posted by IanHarvey


<SNIP>

1. Assume we have two parallel conductors 3mm apart, carrying

<SNIP>

In other words, the effect of 'magnetostriction' on typical audio signals is comparable to putting a 25,000Mohm resistor across your tweeter.

You forget (or deliberatly omit) two facts. Often conductors are closer than 3mm and the dominant part of the Z in Speaker Cables tends to be L, not C (or R).

So, the effect in a given specific case on the capacitance is covered, on the inductance (more important) not yet.

Sayonara

[ThorstenL]

Konnichiwa,

Originally posted by Pjotr


In other words claiming something to be true and it IS true until somebody disproves it? Reverse/upside-down reasoning

Hardly. Maybe you need to read the thread.

My point is that there is in the US (and specifically in the US as I note) a group of people that has in effect "declared war" on the High End industry and has been of decades attempted with dubious methodes (including poorely implemented and incorrectly statistically analysed ABX Tests) to make public the notion that many of the claimed sonic differences in High End Audio are non-existent.

I take STRONG exception to the actual tests set up, conducted and published in support of this "everything sounds the same" position and for many perfectly good and scientific reasons.

So, at the moment there is no public domain data I would consider fully acceptable to either accept or reject the presence of audible differences. In absence of universally acceptable public domain data each and every individual will have to make her or his own mind.

I prefer to make up my mind based on personal empirical study (not just about audio and audio cables) and I recommend the same process to others.

Of course, it is much easier to simply adopt another persons opinions as ones own, however doing so is a simple act of faith equal to that made by an atheist or theist on the eXistenZ of the divine, something I find adequate for my spiritual state of mind with regards to the suprasensual world (whose eXistenZ can be stipulated but neither proven or disproven).

Yet I do not find this simple believe adequate when it comes to issues that are open to empirical analysis and I equally suggest to others that simple "believe" is not adequate. That's all.

So, instead of lengthy theoretical talk about the whichness of the why I recommend the most basic emirical process which will take less time and generate much more reliable and hard data than has been seen in this whole thread.

Sayonara

[SY]

It suffices to me to know WHO and WHAT kind of articles they routinely reject to know not to bother.

Could you please give some specifics? The tacit claim that AES reject properly done papers that somehow "disagree" with conventional wisdom is a grave one and ought to be examined.

[SY]

In other words, the effect of 'magnetostriction' on typical audio signals is comparable to putting a 25,000Mohm resistor across your tweeter.

That is exactly why KYW's work is so potentially important. Here's a guy who has some experimental results that could shake our understanding and open up new fields of research. We need to do what we can to get him to do the right thing and share this discovery with the world.

[ThorstenL]

Konnichiwa,

Originally posted by SY


Could you please give some specifics? The tacit claim that AES reject properly done papers that somehow &quot;disagree&quot; with conventional wisdom is a grave one and ought to be examined.

For starters talk to Ottala.

There are a few other Amplifier Designers too who had real papers rejected on the grounds that their comments did not agree with one or other paper previously published, which of course was the main point to start with.

Now I do not normally move in AES circles (too many uniformed boneheads who ave interest only in keeping the status quo) so I only get to hear about the occasional item, which is really the tip of the iceberg.

Of course, this should not be surprising, as the AES is in effect a lobby of a certain group and the JAES the Lobbys "speech organ".

If anyone truely believes the AES (as an organisation) is about fostering free, unfettered and detailed research into audio they may find themselves with a rude awakening. Since about the 1950's this has not been the case in many fields. Current research is almost exclusively in data compression and surround sound.

All else is subject to scrutiny by the "comitee for un-aes activities", headed up by McCarthy (this a pun I might add, but the principles are the same).

Sayonara