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Description

This instrument features non-real time rendering of bowed string sounds with the effects of string stiffness, bow force and friction between the bow and the strings. It also accounts for the effect of torsional waves on the bridge side and on the finger side and dispersion simulation. The algorithm is based on recent research done by Serafin, et AL, on matlab, pd and stk implementations. This instrument is optimized for frequencies or rather tones inside a 100Hz and 600 Hz range depending on the radio of its parameters. Its design allows for timed envelope style manipulation of most of its parameters.

One advantage in contrast to its real-time counterpart is that it can render chords and various string effects with great detail. Successful testing on tremolos, spicattos, dynamics related to bow pressure, glissandi and extended durations have been performed making it suitable for algorithmic composition. It is then possible to experiment with unusual temperaments and it is possible to create a variety of sonorities which can be used in conjunction with real time performance or as a tape part by itself.

Being part of the Common Lisp Music gives this instrument the option of being modular and extensible. More filtering and reverberation signal processing as well as spatializing parameters can be added on the fly. This clm instrument may act as a solo instrument or as an ensemble of instrument of the string class. Heuristics from Common Music have been tried with good musical results.

The most important constraints of this implementation are the the rendering of vibrato related effects mainly because of its previous sample dependency. Also there are many real time effects not possible mainly because of the lack of performance feedback. Computation and processing time are expensive because of the nature of the sort of bi-quad resonant filters in the model and because of its delay lines however in favor of very good resemblance to the real string.

A good thing about rendering sounds is its accurateness to the per sample basis. Sound and musical expression can be render to a great detail in ways barely possible in a real time performance.

Parameters: vb, vh, fb




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Next: Conclusions Up: Strad.ins a Bowed String Implentation in Previous: Strad.ins a Bowed String Implentation in

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