Article entitled "Inaudible High-Frequency Sounds Affect Brain Activity"

[guiller]

Surfacing through the internet I´ve came across this article:

http://www.arraytherapeutic.com/library/articles/JN83-6-3548.pdf

I am unable to judge anything about the quality of the authors or the claims stated in this paper, but I´ve found the content at least provocative and amusing and therefore it is perhaps worthwhile of sharing it with some fellow AKers.

All the best

PS: sorry if this is a repost

 

[Pyrrho]

It isn't new, but it is controversial:

http://en.wikipedia.org/wiki/Hypersonic_effect

A very relevant quote:

System non-linearities (present to varying degrees in all audio reproduction electronics, speakers, etc.) are known to produce lower-frequency intermodulation products when the system is stimulated with high frequency signals.

Whenever a speaker is fed a frequency, it will also produce other frequencies above and below that frequency (which is distortion). Since some are below, you will often get audible frequency distortion from a frequency that is not itself audible. You can also do the same thing at the low end of the audio spectrum, by feeding a frequency too low to be audible to a speaker, which will also produce higher frequencies than what is fed to it, which are in the audible range.

 

[Drifting]

That must be the reason why FM is so good to listen to when you feel like you're going insane. Less inaudible high-frequency sounds. :yes: