Originally Posted by billybob_jcv
As long as we aren't going to try to make absolute judgments based solely on differences measured under questionable test conditions, then count me in!
Have you got a Windows PC that you can listen to music on? If you do, then why not try out some null tests for yourself? You can decide whether your test conditions are questionable or not!
I posted this in a different thread, but I think it bears repeating here. Here's a nifty program that you can use to conduct null tests: http://www.libinst.com/Audio%20DiffMaker.htm It's free. It's less than 2 megs. Why not download it and take it out for a spin? The author even includes ready made "dyf" files to play on it so you too can hear the differences between different things: http://www.libinst.com/diffmaker_example_files.htm It's fairly easy to play the dyf files (heck, I figured it out!). Just be sure to click the "All-functions" choice in the menu bar so that it reads "Play-only" so you can load the dyf files and then extract the difference track between them.
I especially recommend trying out the test tracks in the "...and a listener challenge" section of the dyf downloads. It's a choir singing Brahms' "Lullaby" albeit with one of the tracks having a brass band playing a Sousa march mixed in. The Sousa march is obvious once you extract and play the difference track.
A lot of the "golden ears" insist that ears are the most sensitive test equipment, that human hearing can detect things instruments cannot. The null test is an objectivist broadside into the subjectivist position that ears are superior to test equipment. If you can't hear the brass band playing, and I'm guessing most folks can't, then it's pretty clear that test equipment is more sensitive than human hearing.
I think the Audio Diffmaker could be a very interesting tool to employ in audio reviews. You say your fancy power cord makes a "night and day" difference in a stereo? First use Audio Diffmaker to show me that there's any difference at all and then maybe we'll talk. I know that for me personally, if I can't hear the brass band while the choir sings, and I can't, then I'm not going to worry about things like whether the jitter in a DAC is -105 db, or -110 db. If I don't have golden ears then there's no point in me paying golden ear prices!
Speaking of golden ears, perhaps the Audio Diffmaker could be used to test not just components, but golden ears themselves? Can the golden ears reliably identify the track with the brass band at -75 db? at -80 db? at -90 db? We frequently have golden ears insisting there are differences between amplifiers with ruler flat response and THD+N well below -100 db. Shouldn't they first be able to demonstrate that they have golden ears, and just how golden their ears are, before we take their word on the differences between components that seem to have no measurable differences?