A cable experiment for non believers...

[gmgraves]

Oh, I agree, but I also think that ears are a reasonable measuring tool to use for these kinds of measurements. As well as a scope. I don't trust the scope any more or less than I trust the ears. Either one or both can easily be in error.

 

Paul

 

While it is true that the ear itself should be a decent measurement tool, and in and of itself, it might well be, but unfortunately, as human beings few of us (read that: "none of us") can adequately divorce our hearing from other cognitive processes occurring in our brains.

 

Nobody is free of what is called "expectational bias". This is the bias that comes from us expecting the more expensive or the better looking component (whether a piece of equipment like a CD player or a DAC, or a length of interconnect cable) to sound better than the cheaper or uglier component. It's the old "I just paid $500 for this 1-meter hunk of cable, it damn well had better be an improvement over what I'm replacing with it!" Of course it will. You EXPECT it to, and so it does. This is often a subconscious "battle" going on in our heads. Many times we aren't even aware that this thought process is occurring. This disqualifies our ears from being useful analytical tools, unless we employ them in a bias-free situation. This is what ABX and Double-blind tests strive to do. Even so, I'm not 100% sure that even the most perfectly set-up of "bias-free" tests are all that accurate.

 

Case in point. Several years ago some analysts at Waterloo University of Canada set up an ABX test that was taken, ultimately, by hundreds of students. In the test an analog musical recording was digitally encoded and decoded and then the decoded signal was re-encoded and this process was repeated a number of times so the end result was the playback or the musical number that had gone through a score or so ADC and DAC loops. This was ABX'd with the original single ADC/DAC loop of the musical number, and the results were that NOBODY could tell the difference between the sample that had been encoded/decoded multiple times and the sample that had been digitized and converted back to analog only once. The conclusion was that the analog-to-digital/digital-to-analog conversion process was so perfect, so transparent, that there is no audible difference between music that had been re-digitized over and over again and music that had only been digitized once and by extension, all ADCs and DACs imparted no sound of their own and were all perfect.

 

Gentlemen, we KNOW that's simply not true, yet the methodology described for this test seemed to be rigorously executed and beyond reproach.

 

George Graves

[wgscott]

I was not thinking of you Bill, or anyone in particular.

 

This is the trouble with having initials "BS". Hence the "wgscott"

[sjoc2000]

Now, there is discussing how many angels can dance on the end of a pin, then there is looking at the tip of the pin to see...

 

This is a simple exercise in looking at the end of the pin. :0)

 

I know many of you do not have a system that lends itself to this test, but those of you who use an inexpensive s/pdif coax cable because you believe it doesn't make any difference, just go get a 1/4' video digital cable and stick it in your system, go sit back in your easy chair and listen. Any difference? Then let us know...

 

Jim

[mayhem13]

Now, there is discussing how many angels can dance on the end of a pin, then there is looking at the tip of the pin to see...

 

This is a simple exercise in looking at the end of the pin. :0)

 

I know many of you do not have a system that lends itself to this test, but those of you who use an inexpensive s/pdif coax cable because you believe it doesn't make any difference, just go get a 1/4' video digital cable and stick it in your system, go sit back in your easy chair and listen. Any difference? Then let us know...

 

Jim

 

......see now....it's been built up way too much now where expectation bias will undoubtedly produce a false positive or negative UNLESS you employ a friend to perform the test blind.......and we know what will come of that!

[4est]

......see now....it's been built up way too much now where expectation bias will undoubtedly produce a false positive or negative UNLESS you employ a friend to perform the test blind.......and we know what will come of that!

 

Buzz kill!

[mayhem13]

Buzz kill!

 

Just keepin it real yo!

[sandyk]

......see now....it's been built up way too much now where expectation bias will undoubtedly produce a false positive or negative UNLESS you employ a friend to perform the test blind.......and we know what will come of that!

mayhem13

It may come as a surprise,(not likely) but not everybody needs blind tests to come up with the correct answer.(smile)

Did you do a series of blind tests with your various speaker, room modifications and equalisation projects before and after ?

Perhaps you felt that the differences were so obvious ( most likely were) that you didn't feel the need to ?

I would be surprised if someone of your experience doesn't have a fairly good longer term auditory memory compared with the average person, just like Barry Diament and many others do.

Kind Regards

Alex

[mayhem13]

Sorry Sandy, my post had a slight sarcastic intention which didn't translate correctly. I had, or have NO intention of debating or discussing blind testing.

 

And yes, as you mentioned I was completely confident at the difference I was hearing and felt no need to conduct a blind or AB test.

 

That being said, my 'rationalle' and knowledge won't allow me to attempt a further 'upgrade' with interconnects as I'm doubtful of any more improvements in performance.

[wgscott]

Gentlemen, we KNOW that's simply not true

 

Are you being rhetorical, or do you really think this?

 

Also, what about the female readership?

[The Computer Audiophile]

The only cable measurements some people need are already on the package - 1 meter, 2 meter, etc.. I couldn't help it :~)

 

Please keep this post on topic and impersonal or we'll have to lock it up.

[4est]

A 2 meter balanced barkeep, the single ended is a bit hoppy for me!

[Stever750]

I'd be intrigued to know how many users there are with Chord DACs with any different interconnect cable experience, both optical and USB

[sjoc2000]

I have finally found a useful article, that discusses "digital" impedance mismatch and the consequences. For those of you who are concerned with this subject, while the article is not wholly specific to audio, you may find the writing useful.

 

http://www.te.com/content/dam/te/global/english/industries/enterprise-network-solutions/knowledge-center/documents/enterprise-white-paper-impedance-maching-in-digital-coax-systems-106093AE.pdf

 

In the meantime, back to pragmatics, there is nothing like the simple test described here to see if differences occur in your system.

 

Jim