Re: maximum 'tatum' speed perception

[beauchamp james w <j-beauch@xxxxxxxxxxxxxxxx>]

> On April 3, 2002 Brian Whitman <bwhitman@MEDIA.MIT.EDU> wrote:
> Has there been any human-testing work on the maximum amount of discrete
> musical events a person can identify in a second? At what point should a
> machine listener (who obviously could do better) stop perceiving rapidly
> played notes or percussives?

I think this would be difficult to test, but I believe Milton Babbitt
did some informal testing in the 60's and 70's. You could do some pattern
matching, but I don't know that that would prove the listener "heard" all
or a certain percentage of the actual notes. On the other hand, some
musicians are able to take dictation of extremely fast passages, e.g.,
a lot of fast bebop jazz has been transcribed. However, transcribers can
employ tricks such as slowing down the sound with a variable speed
recorder or repeating a passage over and over again, until he/she "gets
it right". Pitch detector programs could also be employed, and in many
cases they work very well.

> At extremely high LFs (20Hz) we'll start perceiving tones, and in
> playing-around testing on my computer I could hear quarter note snare
> drums up to 800bpm (so, about 13Hz). Is this a function of musical
> training, the sounds being played, or mechanics of the ear?

Probably all three. My personal impression is that our ears have
evolved to decode in some sense the fastest things that humans can play,
which probably tops out around 20 pulses per second. But perhaps this
varies with fundamental frequency of the source, since it takes less
time (shorter duration) to establish a definite pitch at higher
frequencies than at lower ones. Listening experience definitely
improves ability to appreciate and recognise virtuostic performances
and recognize patterns within these performances that without
experience would probably sound like a random clutter of notes.

Recently I've seen two papers that might relate to your question:

Jarno Seppanen, "Tatum Grid Analysis of Musical Signals", Proc. IEEE
Workshop on Applications of Signal Processing to Audio and Acoustics
2001, pp. 131-134.
Jean Laroche, "Estiating Tempo, Swing and Beat Locations in Audio
Recordings", Proc. IEEE Workshop on Applications of Signal Processing
to Audio and Acoustics 2001, pp. 135-138.M

Jim Beauchamp
University of Illinois at Urbana-Champaign
j-beauch@uiuc.edu
http://www.staff.uiuc.edu/~j-beauch