An electronic violin with a singing formant
M. V. Mathews · The Journal of the Acoustical Society of America · 1982
An electronic violin has been constructed with a resonance similar to the singing formant which Johan Sundberg discovered in the voices of good singers. The formant, as used in the electronic violin, is at 3000 Hz and has a relatively broad bandwidth of 2000 Hz. The formant strongly enhances the perceived liveness of the tone. The violin contains four ceramic microphones, one for each string, mounted in the bridge. Signals from the microphones are amplified by four separate amplifiers and are radiated from four separate loudspeakers in order to avoid intermodulation between strings. The radiated signal is the sum of the signal directly from the microphones and an adjustable amount of signal passed through a 3000-Hz resonance. With the most pleasing adjustment, about a 6-dB peak of 3000 Hz is produced by the resonance. There is some evidence that good acoustic violins have similar peaks.