AI and gamelan ensembles
A gamelan is an Indonesian ensemble consisting mainly of bronze gongs and metallophones, in both cases instruments in which metal plates are made to sound using mallets. Strictly speaking, these are percussion instruments. The metal plates have different pitches, allowing melodies to be played. Ensembles differ in their tuning, that is, their fixed pitches, as well as in the characteristic sound of individual instruments. The pitches are carefully selected by the trained ear of the instrument makers. This is where AI comes in: It can distinguish between and identify different ensembles by their overall sound, which results from the interplay between the pitches used and the sound of the individual instruments, forming something like the fingerprint of an ensemble.
Mapping Gamelan with AI
On the Kohonen maps, you can see how the AI sorts gamelan music. The dots on the graph indicate the individual pieces of music. The different colours represent different ensembles. The shapes indicate the origin of the ensembles.
Touch the dots to listen to the music!
In the map on the right, the AI has sorted the pieces according to the spectrum, while on the left, various sound properties, so-called “psychoacoustic parameters”, have been taken into account. Operate the switches at the top left, and you can see how the individual musical parameters are distributed on the map (yellow here stands for a strong expression).
References
Bader, R. (2006). Transient Finite-Difference Modelling of geometrical nonlinearities of a Balinese Gender dasa Plate. DAGA 2006, 601-602.
Jones, M. E., Gee, K. E., Grimshaw, J. (2010). Vibrational characteristics of Balinese gamelan metallophones. JASA 127 (5), May 2010.
Wendt, G., Bader, R. (2021). Analysis and Perception of Javanese Gamelan Tunings. In: Bader, R. (Ed.). Computational Phonogram Archiving. Heidelberg: Springer.