90--110 DB (very OT)

[Bill Ballard]

At 9:56 PM +0000 12/1/02, Nathan Bower wrote:
>I have heard that organs can create beat frequencies below the normal
>percieved cutoff of the human ear (5-10hz). Does this fit in with what you
>are saying?

Any two frequencies 5-10 HZ apart will create beat pulsations 
identical to the difference in their frequencies. Ya ever tune a 
piano?

>Do we just 'imagine' the very low frequency, or does it really
>exist?

Sarah put quite clearly. It's an amplitude modulation in the 
summation of two frequencies which are separated by 12-15Hz (the 
frequency at which the human brain turns a pulse into a tone), but 
most importantly, which themselves are with in our hearing range.

>N

B

(as long as I don't sign my name, i can talk anyway i like.)