Re: About importance of "phase" in sound recognition

["James W. Beauchamp" <jwbeauch@xxxxxxxxxxxxxxxxxxxxxx>]

The subject title says "recognition", which is a lot different than
"discrimination", but I don't get the sense that recognition is all
that people are talking about on this thread.

To me, the definitive paper on phase discrimination on steady-state
complex tones was by Plomp and Sieeneken in 1969:

R. Plomp and H. J. M. Sieeneken, "Effect of phase on timbre of complex 
tones", J. Acoust. Soc. Am. 46, No. 2 (pt.2), 409-421 (1969).

The prototype signal was a sawtooth but with only 10 harmonics in the
Fourier series. Phase angles on the harmonics were random multiples
of pi/16. The conclusions were:

(1) The timbre difference between a tone consisting of only sine or
cosine terms and a tone consisting of alternative sine and cosine
terms represents the maximal possible effect of phase on timbre;
(2) the maximal effect of phase on timbre is quantitatively smaller 
than the effect of changing the slope of the amplitude pattern by
2 dB/pct and is less for higher than for lower frequencies; 
(3) the effect of phase on timbre appears to be independent of the 
effect of amplitude pattern and of the loudness factor.

There have been a lot of papers about the importance of phase in
musical contexts. Here are a couple:

T. H. Andersen and K. Jensen, "Importance and representation of phase
in the sinusoidal model" J. Audio Engr. Soc. 52, No. 11, 1157-1169 (2004)

S. Dubnov and X. Rodet, "Investigatioi of phase coupling phenomena in
sustained portion of musical isntruments sounds", J. Acoust. Soc. Am.
113, No. 1, 348-359 (2003).

Jim Beauchamp
Univ. of Illinois