29 Jan
2006
29 Jan
'06
8:41 a.m.
fons adriaensen <fons.adriaensen(a)skynet.be>be>:
There are certainly instruments that produce sound
well
above 20 kHz. Now to get 'beats' between two of those
requires something non-linear - just summing them is not
enough. Our ears are non-linear at high sound levels, so
in a real performance this could happen. But I don't
think it will be noticeable at any sane sound levels.
Still don't understand the non-linear part here :/
I make 2 audio files with 400 and 500 hz sine tones and play
them along (out of ardour). There is clearly audible beat
frequency, a 100 hz hum and harmonics of that. Checked with
jaaa: Adding a 99 hz tone to the mix results in another 1 hz
beat frequency.
Found
http://hyperphysics.phy-astr.gsu.edu/hbase/sound/beat.html
and there seems to be no reference to non-linearities that
would be crucial for the phenomenon to come up.
I seem to be missing something obvious and maybe you can throw
another much appreciated explanation at me?
--
Wolfgang