Experimental Demonstration of the Modification of the Resonances of a Simplified Self-Sustained Wind Instrument Through Modal Active Control

Abstract

This paper reports the experimental results of modifying the resonances of wind instruments using modal active control. Resonances of asimplified bass clarinet without holes (a cylindrical tube coupled to abass clarinet mouthpiece including areed)are adjusted either in frequencyorindamping in order to modify its playing properties (pitch, strength of the harmonics of the sound, transient behaviour). This is achievedusing acontrol setup consisting of ac o-located loudspeaker and microphone linked to ac omputer with data acquisition capabilities. Software on the computer implements an observer (which contains am odel of the system)a nd ac ontroller. Measuring and adjusting the transfer function between the speaker and microphone of the control setup enables modifications of the input impedance and the radiated sound of the instrument.

The bodyless sound and the re-embodied sound: an expansion of the sonic body of the instrument

“…It consists of 'a way of modifying the way in which a mechanical system vibrates, with the help of sensors, actuators and a controller' (Meurisse, 2014: 4). 13 The author developed a trombone mute and a simplified bass clarinet (Meurisse, Mamou-Mani, Benacchio, et al, 2015 seeking to apply the concept of active control. Meurisse and the IMAREV team were able to demonstrate that it is possible to change the perceptual sonorities of wind instruments by applying active control techniques using a microphone, loudspeaker, and an analysis/synthesis system.…”

“…Meurisse and the IMAREV team were able to demonstrate that it is possible to change the perceptual sonorities of wind instruments by applying active control techniques using a microphone, loudspeaker, and an analysis/synthesis system. This approach, used in combination with Paul Clift's Acoustic Aggregate Synthesis, allows for the transformation of the bass clarinet timbre, simulating the timbre of other instruments through a hybridisation of acoustic sound and synthesis (Meurisse, Mamou-Mani, Benacchio, et al, 2015 This hybridisation is perceptually possible only when the source of the synthesis emanates from the acoustic instrument, or, in the case of smaller instruments that cannot house a loudspeaker, such as a flute, in close proximity.…”

An active mute for the trombone

“…Active control using gain and phase shifting has also been used to globally modify the resonances of a simplified clarinet (with all resonances affected by the control) 13 . Meanwhile, modal active control has enabled individual resonances of a clarinet to be controlled separately in simulations 14 and experimentally 15 .…”

Modal active control of Chinese gongs

“…Since modal control relies on linear models of the structures, it is particularly suited to instruments that maintain a linear behavior in regular playing conditions. The studies of Benacchio and coworkers 5,6 and Meurisse et al 7 are successful examples of experimental modal control applied to a guitar soundboard and a simplified clarinet, respectively.…”