Discrimination of musical instrument sounds resynthesized with simplified spectrotemporal parameters
Résumé
The perceptual salience of several outstanding features of quasi-harmonic, time-variant spectra was investigated i
n musical instrument sounds. Spectral analyses of sounds from seven musical instruments (clarinet, flute, oboe, tr
umpet, violin, harpsichord, and marimba) produced time-varying harmonic amplitude and frequency data. Six basic da
ta simplifications and five combinations of them were applied to the reference tones: amplitude variation smoothin
g, coherent variation of amplitudes over time, spectral envelope smoothing, forced harmonic frequency variation, f
requency variation smoothing, and harmonic frequency flattening. Listeners were asked to discriminate sounds resyn
thesized with simplified data from reference sounds resynthesized with the full data. Averaged over the seven inst
ruments, the discrimination was very good for spectral envelope smoothing and amplitude envelope coherence, but wa
s moderate to poor in decreasing order for forced harmonic frequency variation, frequency variation smoothing, fre
quency flattening, and amplitude variation smoothing. Discrimination of combinations of simplifications was equiva
lent to that of the most potent constituent simplification. Objective measurements were made on the spectral data
for harmonic amplitude, harmonic frequency, and spectral centroid changes resulting from simplifications. These me
asures were found to correlate well with discrimination results, indicating that listeners have access to a relati
vely fine-grained sensory representation of musical instrument sounds.