two discreet sets of identical frequ. fire rates (Peter )


Subject: two discreet sets of identical frequ. fire rates
From:    Peter  <pfreihof(at)OPTUSNET.COM.AU>
Date:    Mon, 5 Aug 2002 16:25:15 +1000

Hello folks, I'd like to briefly introduce myself. My name is Peter, I'm a "hummer" devoting part of my spare time to investigating this phenomenon. As a matter of fact, I can measure 24 Hz sound components in the surrounding environment at my home. There are also 24 Hz vibration components in the earth, as I can pick up these vibs on the walls (aerated concrete). Although it is impossible to have two discreet sound waves of the same frequency (but differing phase) impeding on one point in air, it would be possible to have one sound wave of 24 Hz in the air, and the other vibrational wave in the soil (of the same frequency) which then could be of a different phase. Since these two discreet 24 Hz waves could meet up on the basilar membrane, this could lead to a unique situation in which a 72 Hz fire rate could result. If you looked at a 24 Hz pulse train, then shifted it in phase by 120 deg, and again by 240 deg, the resulting pulse train would be indistinguishable from a "real" 72 Hz pulse train. Lets say, the vibrational and acoustic components are spaced apart by 120 degrees. This would probably result in two discreet sets of neurons firing at the 120 zero crossings. Now, where would the third "240" deg phase shifted pulse train come from? Could it come from an "amplifying OAE", which results from the randomly generated 24 Hz firing pulses of the neurons not yet locked into phase of one of the previous 0/120 deg pulse trains? Which means, that every time some random fire pulse hits the missing 24Hz/240 deg spot, there could be - for a brief time anyway - a perfect 72 Hz pulse train appearing at the audio cortex which then could trigger an OAE at 72 Hz (which itself is in phase with the "missing" 240 pulse train). This positive feedback loop would start a magnitude increase of the 72 Hz oscillation until enough neurons are locked in, to create a pseudo audible 72 Hz hum illusion. Thanks for your time to consider my thoughts, and I'm looking forward to hearing your opinion on this. cheers, Peter.


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