A suggestion for a blind cable test
Jul 16, 2009 at 7:40 AM Thread Starter Post #1 of 19

gotchaforce

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A year or two ago on head-fi someone mailed out cables that he built with certain materials in it... and then asked people to identify each.

I think an easy double blind test can be achieved using a same sort of setup. What someone does is build 4 pairs of cables, 3 of them are very cheap cables. 1 of them is a very high end cable with silver or something in it. put a tubing around each cable with the same thickness so you cant differentiate based on build. tape the pairs together, throw them in a bin and then mix them up and take them out 1 by 1, labeling them 1 thru 4. That way you dont know which cables are which. Have the cable believer (or yourself i guess) listen to the cables and try to find out which one is the high end cable. Once you have recorded your guesses disassemble the cables to find the high end one.

i dont know just throwing it out there really.. i dont know anyone who believes in cables to administer this test to
 
Jul 16, 2009 at 9:15 AM Post #3 of 19
Quote:

Originally Posted by deadly55 /img/forum/go_quote.gif
please read this do not discuss dbt


Welcome to the Sound Science forum, the only place on head-fi where endless discussions on DBT are still allowed.
 
Jul 16, 2009 at 3:17 PM Post #4 of 19
There are many ways to set up blind tests, and honestly, you don't even need a double-blind test in this area because I don't believe anybody has ever passed a well-designed blind test. It's easy enough to just have a friend change out your power cord while you are blindfolded and run 20 trials.

The problem is that no believer is ever willing to do that because (a) "the differences are so obvious that only a deaf person would not hear them and therefore I will not waste my time"; (b) "I ain't gotta prove nothing to nobody"; (c) "these tests don't mean anything because of course you can't identify a difference in a high-pressure, high-stress testing situation; you need to have some time to soak the cable in and when you are trying to figure out which cable is which you stop hearing the very obvious differences that are there."*

Moral of the story: you can come up with these tests all you want, but nobody is willing to take part. There is a reason why there is only one forum of the dozens of forums here that you can even discuss science. Most audio websites don't even have a place like this. There aren't many other fields where people would be willing to spend tens of thousands of dollars without having some proof, some scientific, measurable basis for picking one item over another. ("I know that both of these microwaves have the same specs--1000 watts--and the same features, but trust me, food tastes better after three minutes in this $2500 microwave than this $50 one. Only an unsophisticated trailer-trash could not taste the difference.")

* That last one is my favorite because when they are reviewing the cable, they always say "the differences were not subtle and could be heard immediately. Within 30 seconds, I realized that I could never go back to listening to my old [power cord/interconnect/digital cable] again because it sounds so [muddy/bright/undetailed/dark]
 
Jul 16, 2009 at 3:45 PM Post #5 of 19
Yes, Edwood did a test very similar to this. I don't have time to dig up the thread now, but it's there if you search.

IIRC, the results came back statistically no different from guessing.
 
Jul 16, 2009 at 4:54 PM Post #6 of 19
Quote:

Originally Posted by seacard /img/forum/go_quote.gif
"I know that both of these microwaves have the same specs--1000 watts--and the same features, but trust me, food tastes better after three minutes in this $2500 microwave than this $50 one. Only an unsophisticated trailer-trash could not taste the difference."




Don't forget to upgrade the the handle to solid silver and get a cryopowercord/conditioner made from unobtainium. Your food will taste like it was "made by angels in heaven*"!!!

* Assuming you are using the proper microphile approved eating utensils to enhance the palate synergy. Can't forget that.
 
Jul 16, 2009 at 5:02 PM Post #7 of 19
Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif
Yes, Edwood did a test very similar to this. I don't have time to dig up the thread now, but it's there if you search.

IIRC, the results came back statistically no different from guessing.



I don't think this is correct. Or at least, there was a lot of dispute about what the results were. As I recall, the skeptics argued the tests proved that people could not identify the silver cable vs. the RS cable, etc. The believers argued that the tests showed that people found to a statistically-significant probability that certain cables sounded different, even though they could pick out the one that was silver, for example.

The argument went on for days and pages. Nothing was resolved. Everybody basically concluded that anyone who didn't agree with their point of view was a complete and utter fool.
dt880smile.png
 
Jul 16, 2009 at 10:08 PM Post #9 of 19
I can't find a good description on that thread of what the protocol was, but the following seems to be true:
  1. The listeners had nothing to base there responses on. They were supposed to identify the silver cable, but had not listened to it sighted before hand.
  2. There was one trial per listener. That means the test is worthless statistically. Depending on the modeled value of p (the probability that a listener gets the right identification) you might need up to 100 trials per listener to reduce type II error to something reasonable.
 
Jul 17, 2009 at 10:38 AM Post #10 of 19
Quote:

Originally Posted by mike1127 /img/forum/go_quote.gif
I can't find a good description on that thread of what the protocol was, but the following seems to be true:
  1. The listeners had nothing to base there responses on. They were supposed to identify the silver cable, but had not listened to it sighted before hand.
  2. There was one trial per listener. That means the test is worthless statistically. Depending on the modeled value of p (the probability that a listener gets the right identification) you might need up to 100 trials per listener to reduce type II error to something reasonable.



Mike

Do you know how big the audible difference was between cables? Was this a super subtle thing, or was it past the JND?

USG

USG
 
Jul 17, 2009 at 10:45 AM Post #11 of 19
Quote:

Originally Posted by upstateguy /img/forum/go_quote.gif
Mike

Do you know how big the audible difference was between cables? Was this a super subtle thing, or was it past the JND?

USG

USG



That thread had no coherent description of the test. Information was spread all over the thread in different places. So I don't know. Of course some people claim silver "blows away" other cables and under that theory it should have been easy to identify. Other people would say that there is no simple rule that silver always sounds better--that it depends on the construction of the cable and the termination. Not to mention that people's tastes differ.
 
Jul 17, 2009 at 11:01 AM Post #12 of 19
Quote:

Originally Posted by mike1127 /img/forum/go_quote.gif
That thread had no coherent description of the test. Information was spread all over the thread in different places. So I don't know. Of course some people claim silver "blows away" other cables and under that theory it should have been easy to identify. Other people would say that there is no simple rule that silver always sounds better--that it depends on the construction of the cable and the termination. Not to mention that people's tastes differ.


Have you heard cables that sound different enough from each other to be able to hear the differences on a WAV recording from the headphone out?
 
Jul 17, 2009 at 1:53 PM Post #13 of 19
Quote:

Originally Posted by upstateguy /img/forum/go_quote.gif
Have you heard cables that sound different enough from each other to be able to hear the differences on a WAV recording from the headphone out?


I don't know. Cable differences are comparable to DAC differences which means they are probably very small differences in the signal---but more than that, they are differences that aren't characterized well by measurements of DAC performance. So they probably wouldn't be recorded accurately by an ADC, unless perhaps it was a very, very high quality 24/96 ADC. This is speculation, though.
 
Jul 17, 2009 at 3:34 PM Post #14 of 19
Quote:

Originally Posted by mike1127 /img/forum/go_quote.gif
That thread had no coherent description of the test.


If I am recalling correctly, there were two threads. The second, very contentious thread, had the results. There was an earlier thread, I think it was also by Edwood -- and it might have been up to a year earlier, since the cables had to be mailed around the country -- which set forth the protocol in detail.
 
Jul 17, 2009 at 3:52 PM Post #15 of 19
Quote:

Originally Posted by mike1127 /img/forum/go_quote.gif
I don't know. Cable differences are comparable to DAC differences which means they are probably very small differences in the signal---but more than that, they are differences that aren't characterized well by measurements of DAC performance. So they probably wouldn't be recorded accurately by an ADC, unless perhaps it was a very, very high quality 24/96 ADC. This is speculation, though.


I can somewhat confirm this speculation. I have digitized (24 bit/44.1 kHz) the same track from an LP by means of WaveLab and the E-MU 1212M – once with full Silver-Dragon cabling, once with full Zu-Gede cabling (in front and behind the Creek OBH-15 Pre with OBH-2 PS).

After digitization I couldn't distinguish the two recordings, whereas in my headphone system the two cable types make a distinct difference (to my ears).
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