Most structural engineers seek to prevent structural vibrations, instrument builders seek to create sustained structural vibrations.
A nice quote from "Feedback control of Musical Instruments" by Edgar J. Berdahl, G¨unter Niemeyer, Julius O. Smith III.
116 pages. Filled with too many ordinary differential equations, transfer functions and root locus plots for light reading. But if you want some cutting edge ideas about feedback control, the CCRMA thinktank delivers again.
Highlights:
Graphtech makes some bad ass sensors that could be used for termination based control. The first time I've seen that concept. But its possible to put sensors and actuators at the end of the string.
Most types of sensor/actuator will be done digital. This will introduce some type of delay and will cause phase problems. The whole notion of simply adding a microphone and speaker to increase feedback, will probably not sound the way one expects.
Certain types of string activators will result in inharmonic series coming out of the strings.
Magnetic actuators (aka ebow) and more are a nice way to sustain the tone. Magnet activated strings are boring to look at, but magnets provide a nice way to sustain a tone.
Charles Besnainou was footnoted a few times in this paper.
No comments:
Post a Comment