90--110 DB (very OT)

[Richard Moody]

----- Original Message -----
From: Nathan Bower <nathan@bowern8.plus.com>
To: Sarah Fox <sarah@gendernet.org>; Pianotech <pianotech@ptg.org>
Sent: Sunday, December 01, 2002 3:56 PM
Subject: Re: 90--110 DB (very OT)


> I have heard that organs can create beat frequencies below the
normal
> perceived cutoff of the human ear (5-10hz). Does this fit in
with what you
> are saying? Do we just 'imagine' the very low frequency, or does
it really
> exist?
>

I would say 5  to 10 hz is perceived as a beat frequency.  The
beat rate of   C4--E4 is a little over 10 hz or cycles per second.

I have heard two tones, C2--D2  (C4 is middle C) played together
on a pipe organ and a beating resulted that sounded like 8 per
second.  This was called a "resultant".   If you have access to a
synthesizer or digital keyboard that has an organ "voice" on it
that is something like "16+2" or 16+4  play C3--D3  and you will
hear a beat that is like 8 bps.  It is REAL on my Yamaha
SR-340.  ---ric   (the "r" stands for resultants r real)