Modifying Partials for Minimum-Roughness Sound Synthesis

This is the accompanying website to the article [1].

  1. Simon Schwär, Meinard Müller, and Sebastian J. Schlecht
    Modifying Partials for Minimum-Roughness Sound Synthesis
    In Proceedings of the 3rd International Conference on Timbre, 2023. Demo
    author    = {Simon Schw{\"a}r and Meinard M{\"u}ller and Sebastian J. Schlecht},
    title     = {Modifying Partials for Minimum-Roughness Sound Synthesis},
    booktitle = {Proceedings of the 3rd International Conference on Timbre},
    address   = {Thessaloniki, Greece},
    year      = {2023},
    url-demo  = {},


In this work, we introduce and compare two methods to adaptively modify the partials of simultaneously sounding synthesized tones to minimize roughness. By changing their amplitude and/or frequency over time (e.g., for each chord separately), it is possible to dynamically control the timbre of a polyphonic sound in real time. This introduces an additional parameter for sound synthesis that may allow for changing the roughness of a sound without modifying other perceptual attributes of the individual tones, like their fundamental frequency (F0) or loudness. We draw inspiration from choir singers, who may not only dynamically adapt their pitch, but also control their vocal formants (i.e., the prevalence of certain partials) as an additional means to facilitate intonation and voice blending between musicians.

Audio Examples

Synthesized chords with random detuning (+/- 20 cents) and different timbres

D major (D5, A4, F#4, D4), Sawtooth

D major (D5, A4, F#4, D4), Clarinet-Like

A minor (A4, E4, C4, A3), Sawtooth

A minor (A4, E4, C4, A3), Clarinet-Like

E7 (G#4, D4, B3, E3), Sawtooth

E7 (G#4, D4, B3, E3), Clarinet-Like


The International Audio Laboratories Erlangen are a joint institution of the Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and Fraunhofer Institute for Integrated Circuits IIS. This project is supported by the German Research Foundation (DFG MU 2686/13-2).