[AMRadio] Aural Illusion, the Human Voice, Enhanced Amplitude Modulation

Donald Chester k4kyv at charter.net
Mon Feb 3 14:28:24 EST 2014

We are all familiar with optical illusions that use various forms of
trickery to fool the eye. This one uses AURAL (audio) trickery to fool the
ear.  So, how is it possible that this tone ascends in pitch endlessly
without passing the threshold of human hearing? (Hint: Listen carefully; the
pitch never actually ascends.)


Although not exactly the same thing, this may relate to what George W2WLR
was getting at in his "Enhanced Amplitude Modulation" article:

"...It used to be thought that treble audio waveforms had to climb to the
top of bass audio waveforms, as in fig. 9.  Actually, we scan our tones,
from lowest upwards to the highest, about 125 times per second, as in fig.
10. Surprisingly enough, at first learning, the frequencies of our voices
are not the pitch. The pitch is the rate of scanning. A girl will use the
same tones as a man, but she will scan maybe 260 times per second..."


This email is free from viruses and malware because avast! Antivirus protection is active.

More information about the AMRadio mailing list

This page last updated 17 Feb 2018.