Of course we can't forget the blind test between metal coat hangers straightened out and connected to speakers versus Monster cables in which the listeners were told both were Monster cables. The listeners could not detect any difference between the two. In fact, some claimed the coat hangers sounded better.
I'm betting on the coat hangers since ALL the electrons stay bound together in one medium instead of being split across multiple wire strands only to be joined again at the other end. Can you trust that the electrons went back together at the speaker end in the exact same manner as they were sent from the amplifier? Not me!
I agree Bob, we shouldn't drive out the witch doctors, since they help sell products. Audio quality is subjective, and if someone thinks he needs a device that "strips quantum noise energy off the electrons" because to him it sounds better, then by all means someone needs to be there to sell it to him.
The placebo effect is very powerful!
If we started doing engineering tests of all the audio product garbage, we'd be doing ourselves a great disfavor. First, the astonishing claims of "openness, flow, dynamic headroom, interoperable transdimensional frequency displacement, and completion of hyperspacial revolving transportals" would be replace with Bode diagrams. Dull. Next, we wouldn't have the chance to see just who buys a polarized cable to be used in only one direction of sound flow. And there wouldn't be jobs for audio salesmen with better knowledge of beer labels than audio. No, we shouldn't peer too closely into the outer limits of audio accessories. Now look: are there artifacts that are easier to hear than to measure. I'll bet there are. I don't hear as well as a friend of mine, a superior electrical engineer and musician, and when he tells me that there's something wrong with an audio setup, I tend to believe him. On the other hand, he does not believe in either the Easter Bunny or mystical audio effects: he might say "hey, these speakers are really boomy" or "this room has too much in the way of hard walls". I've yet to hear that microscopic cracks in the bearings of a CD player are introducing ultrasonic overtones into the digital playback of anything. But then, he's an engineer, not a retreaded car salesman. To be fair to audio salesmen, I've run into two who seemed to actually know something about their products and music as well. They were a refreshing change. But let's not drive out the witch doctors quite yet: they are sooooooo much fun.