[sdiy] LFO, analog computers

[Thomas Hudson]

In a message dated 2/14/01 1:41:26 PM Eastern Standard Time, matti at devo.com
writes: 
> 1)In trying to produce theta waves in the brain, I wondered if I couldn't
> simply set an oscillator to 4-7 Hz, instead of putting one wave with some
> frequency into one channel, and another with a difference in frequency of
> 4-7 Hz into the other. 

My understanding (which may be wrong) is that you need two separate
frequencies in each ear for the brain to synthesize the difference
and "resonate" to produce theta in the brain. I don't think listening
to 4 hz in mono would produce the same result. I use to experiment
with light and sound machines and had some interesting experiences
producing theta waves. It seemed to cause a lot of forgotten childhood
memories to appear. I've heard this is due to the fact that our brains 
produce mostly theta in early childhood. And of course don't overlook
alpha.

DCMagnuson at aol.com wrote:
> 
> Don't forget, in the 4 Hz range, I think you can cause the listener 
> extreme discomfort, disorientation, confusion and possibly make them 
> sh!t themselves. These frequencies are the ones used for riot control,
> etc.... may want to keep some rags handy ;)
> 
Interesting. I heard that 14 Hz was also a nasty frequency. Something 
about resonate frequencies of the human anatomy. 

> Sorry for straying so far OT... I'll stop now ;)
I find it interesting. Maybe we need "convulsions-diy" :-)

Tomy