Ondes Martenot
This project has a dual focus: museums and science.
The objective for museums in this project concerns the automatic generation of documentation for instruments and simulation code for “non- invasive listening”—important for preserving playable virtual forms—in addition to electronic cloning of ancient technological components as programmable analog components that can be inserted in circuits, an important factor for the preservation of instruments in a non-virtual form.
The scientific objective focuses on physical models of old non-linear electronic components, simulation in real-time with guaranteed passivity of electronic circuits, and automatic generation of documentation and simulation code (work based on Port-Hamiltonien systems—PHS— a very productive formalism for multi-physical systems). It also focuses on the conception of programmable analogical electronic components and the creation of a general methodology applicable to Ondes Martenot and other families of analogical audio circuits.
We made an ergonomic facsimile of the Ondes Martenot n° 169, dating from 1937, intended to show the operation and sound of the instrument to museum visitors. The numerical simulation of the period triode tubes, in the stages of the electronic circuit (heterodyne oscillator, mixer and amplifiers), is based on the PHS formalism.
The digital model is embedded in a real-time digital processor and connected to a user control interface: MIDI keyboard and ribbon position sensor for the pitch, hand pressure control key (Touch, Expressive E) for the sound level. The next steps are to design facsimiles of the original «diffusers».
A measuring bench is currently being developed to characterize the voltage and current responses of the triode lamp models used in the different generations of Ondes Martenot, as well as their ageing. This study will allow to virtually control the degradation of these electronic components and thus to simulate the sound of the instruments at different stages of their life.
This project involves the Musée de la musique, whose approach aims to develop innovative tools for the conservation of its collections and the dissemination of heritage.
IRCAM's team : Sound Systems and Signals: Audio/Acoustics, InstruMents