DBT Report

You tink im dirty, she's the Nurse!!

 

Wolfgang,

I apreciate your reasoned response, it's a shame some of our elder statesmen couldn't have followed suit.

Just out of curiosity (and not to wind everyone up again!), could you confirm that Ted Nousaine is probably the world's leading proponent of the DBT.

 

On the whole I'd agree. I think that two electrically identical (or very similar) cables can certainly not be distinguished and all those standing prizes of $10K or whatever it is for distinguishing two cables in a DBT stipulate the cables must be electrically identical.

I would guess though that most cables are pretty similar in LRC terms, ergo, they are all probably indistinguishable.

I think that you'd need pretty massive variations in LRC for changes to be audible. TBH I think it's far more likely that sockets and connectors/plugs etc can make a much bigger difference than the cable they're attached to. There's a lot to be said for good, clean junctions where metal meets metal in a circuit, not to mention potential electrolysis where there's a junction between two different metals (which could accellerate corrosion of the contacts).

Michael.

 

Actually, no. I don't necessarily agree with this, although I don't necessarily disagree either.

I'm thinking of the sonic differences between two different capacitors which, presumably, have the same capacitance.

I think that it's possible that cables can do more than just act as (often negligible) capacitances or inductances. For example, some cables are shielded, which is a separate issue.

So, I don't know but I suspect that there may be differences even between two cables of the same capacitance and inductance.

On the other hand, maybe there aren't.

Clear enough?

 

For those of you who are interested in this subject, can I suggest you have a read of this .

Flicking through it, I was almost struck by the feeling of Deja vu! I'd never read it before, but I did find it interesting that 6 out of 7 listenerers in a Double blind test correctly identified high end cables

 

Hi Steve

I nearly added ''and other parameters which may also need to be measured'' - like RFI.

I agree that to establish a fair test between two cables you would need to ensure the RFI, EMI, dailactic, conductance, resitance, inductance are both the same. (possibly other parameters Ive forgotten about)

I dont think it would be testing anything if you had ..

cable A) poor inductance, crap resistance, crap capacitance, naff dialectic, wire taken from a chicken coop, badly soldered plugs vs

B) super dooper cable.

...except perhaps that its possible to DIY a really crap cable.

 

I think that the article demonstrates that care must be taken with the precise testing procedure, in order to arrive at results that would be considered meaningful.

We have to be annoyingly neurotic over this as DBTs are, by their nature, 'anal'.

 

From the quote below (have I read it wrong?) they compared a high end cable with something far thinner than a freebie wire?

''To further acquaint the participants with the ABX procedure, the MIT cable was compared over two trials to 30-gauge wire wrap wire. (Thirty-gauge is not much bigger around than a human hair.) The difference between MIT and 30-gauge was gross and audible''

Perhaps 6 out of 7 DBT'ers correctly identified the naff-o-cable?

 

John Atkinson said there was also a considerable loudness difference between the two cables so the test wasn't level matched - an absolute minimum pre-requisite for a valid test. And yes, the who spoke up and said 6 out of 7 is not significant is correct. It may seem counter intuitive (a lot of statistics is) but it's true.

Michael.

 

I felt differently Steve

Seriously though, the article mentions the attendance of the local law enforcement and advertising standards representatives all ready to sue the cable manufacturers, but I have never heard of a case proceeding I suspect the 6 out of seven identifying the correct cabe would have gone some way to address the issue, but it appears even if it did over there, news has not reached blighty yet.

In all seriousness, if it can be proven that it's all a myth and charlatan manufacturers falsly advertising the effects of their products, why has nonoe put their money where there mouse is and sued

Interesting reading to be had also at the ABX site here

So they couldn't tell two cables apart. fair enough. Still I see they couldn't tell two cartidges apart, nor two amplifiers or.....

But they are kind enough to sell you their test equipment and virtual ABX program

 

chris, I think you have misread it. I beleive the successful identification of the high end cable took place at an earlier event organised by this clown, which i understand led to some embarrassment and the creation of a new, more stringent test procedure

 

Well of course you're right. Still this ''and other parameters which may also need to be measured'' is at the crux of the issue for me.

My position is that every aspect of the listening experience can probably be included in the scientific domain of 'the measurable'. The trouble is that so far no-one knows what to measure or the full impact of different measurements on the listening experience.

By all means let's ensure that the cables are equal in terms of inductance and capacitance but if they measure the same in inductance, capacitance, and any other criteria as yet undiscovered, they will of course sound identical. It's the other criteria that we haven't got a handle on yet.

Incidentally, this is not only true for cables but also for amplifiers, cdps, speakers, etc. We don't yet know exactly what to measure and we don't know what weights to give the measurements.

For instance, we can measure the 2nd harmonic distortion of a speaker at say, 1kHz and 20W to be 5% and the 3rd harmonic distortion may be measured to be the same. Nothing in the measurements tells us that most people would find odd harmonics more obnoxious than evens.

The truth is that there is no measuring apparatus currently existing that can even approach the sophistication, sensitivity and scope of human hearing. Millions of years of evolution achieves more than half a century of engineering.

 

The blatant contempt for Dan Dugan by the author of the article (Robert Harley) makes the whole article much less valuable than it could have been. Honestly, trying to suggest that Dugan is on a McCarthyist witch hunt against cable manufacturers is so laughable it's sad. It's also incredible how seriously some people take the issue

Michael.

 

Robert Harley has some giant issues It's a shame he doesn't say where that result came from - I think he may have some problems with statistics too...

 

More interesting reading here

A bit flowerey and highly subjective, but with some valid points I feel.

As for the blatent contempt Michael, I'd have said Dugan himself was clearly guilty of that, dismissing out of hand the possibility that he was wrong, mocking the very people who'd had the decency to turn up and take part.

And again, why no prosecutions if it's all a con? I simply don't understand that

 

Another one here

Why would a cable company produce an ABX comparator

 

Mmm. Again, they don't give any more details about the results they supposedly produced in 1995 'proving' the value of upgrade cables. And given Wireworld's emphasis on the importance of the skin effect, I'm disinclined to place too much faith in them just at the moment

 

Fine. But why produce an ABX comparator? that was the question to be fair, not whether you were convinced by the company marketing

 

I wonder why all of a sudden the cables to be compared have to be equal in R/C/I, RFI, whatever, I thought the point was that all cables sound the same, for instance Ocos and Isolda, standard PC and Eupen, and this is not a shot at Michaelab, it is just because they have been mentioned recently...

In fact I dont think I ever compared cables with the same characteristics, I assume the differences cause the different sound...

By the way, I agree that volume match is a must...

 

Man, this just goes on and on and on.
Pete H good to see you in there
I'll be up for your DBT to