ELdartford sez
OTOH, it's also been established that the audibility of PURE tones diminishes with age in the higher frequencies. So here, we're talking about "sound in context": i.e. say, harmonics of an instrument -- where the fundamental & certain harmonics are well within our pure tone hearing range and some of the related info is outside an individual's "official" (pure tone) audible range.
The strange thing is that our ears work as a low pass; so, some people speculate that it's the COMMON interaural excitation that does the trick...
For this to happen (let's ignore the possible contribution of the bone structure for now) would'nt it mean that our interaural "mechanism" is situated in the DIRECT path (sweet spot) of those frequencies (remember, our acuity falls dramatically, ~20-30db, up there). If so, then moving our head slightly would eliminate this perception.
So, let's assume a super high frequency transducer with excellent dispersion characteristics and thereby eliminate the need for that narrow sweet spot (a Murata is quite good, btw).
It is my contention (but I have no concrete evidence) that three things are happening in conjunction:
a) the high frequency sound is loud enough to overcome our reduced acuity up high (at -60db perception our ear would basically reject it)
b) the sounds in our "official" audible frequency range are rendered more palpable (for wont of a better word) because the super transducer's distortion points (upper resonance) have moved very far away (it's ~100kHz for a Murata) -- hence "perception" of positive effects. This still relates to our "official" range of hearing.
b) there is a combined excitation of aural and other, structural, mechanisms that indicate the presence of high frequencies -- that we cannot, however, qualify or explain (our hearing is a defense and guidance mechanism geared towards perceiving and locating).
Even at B there is a dilemma: in a small experiment in France some subjects were asked to put one ear close to a super tweet and declare whether they perceive anything. Inconclusive (some did, some didn't, no pattern. BTW, I did a similar thing & did perceive energy or lack of it with some DELAY however when the tweet STOPPED producing sound -- joining Eldartford's idea).
Subjects were then asked to move away from the transducer & listen normally (stereo), just by casually sitting on a couch in front of the speakers as one would do at home. Everyone "heard" the supertweet playing. Amazingly, only the s-tweet was connected (at 16kHz -- very high up for sound out of other context).
I find this fascinating.
the ear senses RATE-of-change of pressure (...)Have you heard any other explanationWell, 1) about 20yrs ago a french prof (forgot the name) claimed findings that the bones contribute to our perception of very high frequencies. 2) There seems to be a case for the interaural mechanism working together -- not ONE ear alone, but both being excited.
OTOH, it's also been established that the audibility of PURE tones diminishes with age in the higher frequencies. So here, we're talking about "sound in context": i.e. say, harmonics of an instrument -- where the fundamental & certain harmonics are well within our pure tone hearing range and some of the related info is outside an individual's "official" (pure tone) audible range.
The strange thing is that our ears work as a low pass; so, some people speculate that it's the COMMON interaural excitation that does the trick...
For this to happen (let's ignore the possible contribution of the bone structure for now) would'nt it mean that our interaural "mechanism" is situated in the DIRECT path (sweet spot) of those frequencies (remember, our acuity falls dramatically, ~20-30db, up there). If so, then moving our head slightly would eliminate this perception.
So, let's assume a super high frequency transducer with excellent dispersion characteristics and thereby eliminate the need for that narrow sweet spot (a Murata is quite good, btw).
It is my contention (but I have no concrete evidence) that three things are happening in conjunction:
a) the high frequency sound is loud enough to overcome our reduced acuity up high (at -60db perception our ear would basically reject it)
b) the sounds in our "official" audible frequency range are rendered more palpable (for wont of a better word) because the super transducer's distortion points (upper resonance) have moved very far away (it's ~100kHz for a Murata) -- hence "perception" of positive effects. This still relates to our "official" range of hearing.
b) there is a combined excitation of aural and other, structural, mechanisms that indicate the presence of high frequencies -- that we cannot, however, qualify or explain (our hearing is a defense and guidance mechanism geared towards perceiving and locating).
Even at B there is a dilemma: in a small experiment in France some subjects were asked to put one ear close to a super tweet and declare whether they perceive anything. Inconclusive (some did, some didn't, no pattern. BTW, I did a similar thing & did perceive energy or lack of it with some DELAY however when the tweet STOPPED producing sound -- joining Eldartford's idea).
Subjects were then asked to move away from the transducer & listen normally (stereo), just by casually sitting on a couch in front of the speakers as one would do at home. Everyone "heard" the supertweet playing. Amazingly, only the s-tweet was connected (at 16kHz -- very high up for sound out of other context).
I find this fascinating.