A cautionary tale of self deceit - from a loudspeaker designer
We recently touched on the subject of the wild and ludicrous claims of sonic improvement made possible by changing your speaker cables. We just don't believe it, and nor do those who have conducted proper, blind listening tests. Any differences - and there may well be small differences - are likely to be speaker/amplifier/length dependent which makes universal recommendations useless at best.
It all boils down not to the cables, but to the truly dreadful human audio memory, which is only reliable for a few seconds at best. This has been know for two or more generations and should be obvious. So anyone that can reliably make a mental comparison of two sounds separated by a few seconds will not be able to make the same reliable comparison over thirty seconds, or a minute or five minutes. Or a week or month. To make comparisons between A and B that are reliably within the human audio time zone, the switch-over comparator was invented. Even quality audio was demonstrated and sold via the switch-box (see picture). It fell out of fashion when it didn't suit the media or industry to have such black and white, go/no-go, pass/fail delineations. And that coincided with the end of the golden era of science-based audio reviewing.
That's another story, but I wanted to tell you about my experience these past few days which proves a point. I'm not embarrassed to admit it, because I know just how as humans our senses are useless instruments because we cannot remove the emotion from the observation. Here is a case in point ....
I don't watch much TV, and rarely a DVD but I do have a TV/DVD set-up in a spare room (used to to be the children's play room when they were small). Nobody fiddles with the system, and perhaps once a month I'll half watch something in stereo or surround, sometimes a DVD audio disk. The speakers are the NRG4 towers that we made a few years ago either side of the TV. I sit about 2m away. Now, I became vaguely aware about a year ago that the left speaker seemed a little less bright than the right, and I fiddled with the biwire links and I guess convinced myself that it was working properly. I completely forgot about it, and I've watched a few movies, many TV documentaries, DVD audio disks during the year. But finally, just before the Royal Wedding (April 2011) for some unknown reason I pressed my ear to the left tweeter - nothing. So I fiddled with the biwire links again - still nothing. Fetched a test meter and traced the wires assuming a wiring/xover fault as we'd never had a failure of the NRG tweeter. Wiring around xover good. So it must be the tweeter?
I carefully removed the tweeter to find that the plastic moulding had failed along a weld seam and the terminals had slightly separated from the voice coil/magnet, hence no possibility of sound. And this must have happened many months - perhaps a year ago. So I have been listening to a pair of speakers with a dead tweeter on the left channel and not even noticed it.
How is this possible? It's simple: to a large degree, we hear what we want to hear. This works for and against our listening pleasure. For because it makes the crackles and distortion of all LP listening inaudible as we marvel at the romanticism of the rock wiggling in the grove, and it works against us when we all-too-easily convince ourselves in the sonic miracle of that new (expensive) speaker cable, spikes, room-tuning bells, isolation platforms or whatever. We allow ourselves to be seduced by our own senses. And seduction can be very pleasurable indeed.
Be warned! Your audio memory will hear what it wants to hear.
Alan A. Shaw
Harbeth Audio UK