1) Elõször is hadd gratuláljak ahhoz, hogy templomi kórusban énekelsz. Feltételezem, hogy szereted is a klasszikus zenét, ami manapság elég ritka, ám annál értékesebb tulajdonság. Magam is nagy komolyzene-kedvelõ vagyok.
2) Sajnos már nem emlékszem, hol olvastam a fülkagyló térhallást elõsegítõ funkciójáról, ezért végeztem egy kis guglizást - nem is annyira azért, hogy az igazamat bizonyítsam, hanem azért, mert kíváncsi voltam, jól tudom-e a dolgot. A keresés eredményét alább olvashatod (a spatial hearing kifejezésre kerestem rá), elsõként a The Journal of Neuroscience 2004. április 28.i számából idézek, talán elég megbízhatónak találod, de a többi sem fórumvitákból való:
"Spectral Peaks and Notches. Spectral peaks and notches can provide information about frontback and up-down orientations. Spectral peaks and notches arise due to anatomic and acoustic properties of the human outer ear, which amplifies and attenuates frequencies higher than about 4000 Hz in a direction-dependent manner."
"Obviously the frequency domain perspective on HRTFs corresponds well with classical duplex theories. However, IIDs and ITDs vary in complex ways across frequency because of constructive and destructive interference of the direct wave with sound reflected off the body. Above 4 kHz sound is reflected mainly by the pinnae, and below 2 kHz sound is reflected mainly from the torso. In between there is a region of overlapping influence. The pinna is especially important to spatial hearing and may be considered as an acoustic, linear filter. "By distorting incident sound signals linearly, and differently depending on their direction and distance, the pinna codes spatial attributes of the sound field into temporal and spectral attributes [14]." The frequency dependence of IIDs and ITDs is important to the resolution of front-back reversals and was not captured by Rayleigh’s duplex theory."
"Since the pinna is a more effective reflector for sounds coming from the front than for sounds from above, the resulting notch is much more pronounced for sources in front than for sources above. In addition, the path length difference changes with elevation angle, so the frequency of the notch moves with elevation. Although there are still disputes about what features are perceptually most important (for example, see Han), it is well established that the pinna provides the primary cues for elevation."
"We not only hear sounds to the left or right, but also up or down and near or far. How we do this has been studied for a long time, and although some mysteries remain, the major mechanisms are well understood. For example, it is well known that the primary right/left or azimuth cue comes from the difference in the times at which sound waves arrive at the two ears, and the primary up/down or elevation cues come from the spectral changes produced by the outer ears or pinnae."
Megj.: pinna (többes számban: pinnae) - fülkagyló, ezt keresd az idézetekben.
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