Spectral envelope, not fine structure, determines perceived sharpness

Evidence

Sharpness is a sensation which we can consider separately, and it is possible, for example, to compare the sharpness of one sound with the sharpness of another. Sharpness can also be doubled or halved if variables are available that really change sharpness. The variability of sharpness judgements is comparable to that of loudness judgements. One of the important variables influencing the sensation of sharpness is the spectral envelope of the sound. Many comparisons have indicated that the spectral fine structure is relatively unimportant in sharpness. A noise producing a continuous spectrum, for example, has the same sharpness as a sound composed of many lines if the spectral envelopes measured in critical-band levels are the same. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1340

It is helpful in developing a model of sharpness to treat sharpness as being independent of the fine structure of the spectrum; the overall spectral envelope is the main factor influencing sharpness. In Chaps. 6 and 8, it was shown that the spectral envelope is psychoacoustically represented in the excitation level versus critical-band rate pattern, or in the specific loudness versus critical-band rate pattern. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1351

Categorization

• XREF: Extends the earlier chapters’ treatment of critical-band loudness models to sharpness — same family of percepts scaled by critical-band measures. — connects to: Sharp spectral peaks, not narrow gaps, drive strong pitch perception; Sharpness depends on the spectral envelope, not fine structure; Envelope and fine structure are mathematically orthogonal but not perceptually independent (+1 more)
• corroborated: 4 independent passages support this claim — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1340; Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1351

Broader Connections

• Sharpness depends on the spectral envelope, not fine structure #corroborates (1.00)
• Envelope and fine structure are mathematically orthogonal but not perceptually independent #expands (0.85)