A spectral-envelope synthesis model to study perceptual blend between wind instruments

Sven-Amin Lembke , Stephen Mcadams (1)

1 CIRMMT - Centre Interdisciplinaire de Recherche en Musique, Médias et Technologie [Montréal]

Wind instrument sounds can be shown to be characterized by pitch-invariant spectral maxima or formants. An acoustical signal analysis approach is pursued to obtain global spectral envelope descriptions that reveal these pitch-invariant spectral traits. Spectral envelopes are estimated empirically by applying a curve-fitting procedure to a composite distribution of partial tone frequencies and amplitudes obtained for all available pitches of an instrument. A source-filter synthesis model is designed based on two independently controllable formant filters with their frequency responses matched to the spectral envelope estimates. This is then used in a perceptual experiment in which parameter variations of the synthesis filter are manipulated systematically to investigate their contribution to the degree of perceived blend between the synthesized sound and a recorded instrument sound. The perceptual relevance is assessed through two tasks in which participants either produce the best attainable blend by controlling synthesis parameters or rate the degree of blend for 4 parameter presets. Behavioral data obtained from both experiments investigating common wind instruments across a representative set of pitches suggest the utility of this formant-based model for correlating acoustical description and perceptual relevance, as both formant frequency and magnitude appear to affect perceived blend.

Mots clés: timbre; blend; spectral envelope; synthesis

Domaines: Acoustique [physics.class-ph]

Sven-Amin Lembke, Stephen Mcadams. A spectral-envelope synthesis model to study perceptual blend between wind instruments. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811281⟩