Comment Re:Further Down the Rabbit Hole - A mistake (Score 2, Informative) 561
There is one slight error in your very good writeup on how binaural beats works. What you described, playing two notes on two different sound producers (in this case tuning forks), causes an actual, physical, "beat". The sound waves interfere or combine with one another in physical space, and a new sound wave (or a composite of the two, same difference) is created and propogated through air, the medium of sound.
The binaural beats mentioned here work a little differently, in that a recording is played, and it must be listened through headphones. One ear hears a certain pitch or frequency, the other ear hears a different pitch or frequency. The difference here is that neither ear "hears" a beat, the beat is created entirely in the brain of the listener. I am not a neurobiologist so I cannot explain the exact mechanism, but it appears it has something to do with how the brain processes sound and attempts to internally combine the two different sounds into a single perception/experience for the consciousness.
I checked out some binaural beat programs once. Basicly just sine wave (or fancier) generators that let you pick the frequency for the left output and right output. If I listed on one ear only using headphones, I hear a single frequency. If I listen to both ears, I hear the two frequencies, AND I perceive a beat in addition to that, that only exists in my brain. Its at the very least neat. At the very most I didn't notice any particular effects on myself, and didn't get addicted or anything to it.
The claim or assumption of the binaural beats people is that the low frequency beats can be used to simulate in the brain the delta waves or alpha waves or whatever waves are associated with deep sleep, or relaxation, or whatever. Again I am not a neurobiologist, so I can't say if this does anything.
Playing two tuning forks together or tuning a guitar is pretty neat to me too.