So why do we chase low dist woofers and servo control etc,, if we cant hear it anyway..?!?
The article illustrates the following:
(A) Typical pop music, if played loud enough, sounds pretty much the same regardless of how high the distortions are. It evolved to be that way, so that anyone can listen to it anywhere at any time. Some other genres are very different in this regard - even slightest distortions take their magic away.
(B) Sound objects localization effects are not always taken into account by experiments like that one. For instance, a highly-distorting subwoofer may become locatable in an unwelcome way during "ominous rumble" passages in movies.
A highly-distorting subwoofer may generate hilarious illusions sometimes. For instance, bass guitar player may be perceived as shorter than he or she actually is, because the sound source perceptual location could be shifted downward.
To illustrate: let's say a bass guitar plays open A string at 55 Hz, on a system which includes a subwoofer crossed-over at 80 Hz with 24 dB/octave filter. A low-distorting subwoofer would reproduce the fundamental, some of the second harmonic, and a little bit of the third; the rest of harmonics would not be audibly reproduced.
A highly-distorting subwoofer would add tons of harmonics at 110 Hz and above, which could be readily detected via the shift of the perceived guitar origin closer to where the subwoofer is. Since the effect is frequency-dependent, the bass guitar may appear jumping around or stretching and contracting while playing.
So, one of the reasons for buying low-distorting servo subwoofers is preservation of the bass guitarists dignity. Without good subwoofers, they may audibly appear to be short fat gnomes wildly jumping around the stage, while playing an instrument inexplicably made of rubber