Roughness Minimization Through Automatic Intonation Adjustments

Abstract

We have created a reintonation system that minimizes measured roughness of parallel sonorities as they are produced. Intonation adjustments are performed by finding, within a user-defined vicinity, a combination of fundamental frequencies that yields minimal roughness. The vicinity imposition limits pitch drift and eases real-time computation. Prior knowledge of the tones played and timbres used is not used for execution of the algorithm. We test a proof of concept prototype by adjusting equal temperament intervals rendered with a harmonic spectrum towards pure intervals in real-time. This prototype exemplifies musical and auditory characteristics of roughness minimization by adaptive techniques. We discuss the results obtained, limitations, possible improvements, and future work.

Acknowledgements

For their valuable observations, we would like to thank Jonathan Wild and William Martens at the Centre for Interdisciplinary Research in Music Media and Technology (CIRMMT) in Montréal, Canada, Albrecht Schneider of Hamburg University, and anonymous referees from JNMR.