> Human brainwaves are in Theta (most relaxed) at 6.7 Hz. Frequencies at or
> close to there cause an effect of the brain trying to sync-up with them
> making you very relaxed. There are some tapes and machines designed to
> binaurally beat at these frequencies just for this purpose.
I've done this with a tape--I think it was called the Silva method (years
ago, not sure). It worked wonderfully for deep relaxation.
There are tutorials in Cool Edit (shareware PC audio program available from
http://www.syntrillium.com) that guide you through various "brainwave audio"
exercises; the program has rudimentary synthesis capabilities, so you can
construct an entire session of various waves. It's lots of fun! (must
develop equivalent MOTM patches to put the crowd to sleep at my next gig...)
David.