Audibility of Initial Pitch Glides in String Instrument Sounds

Listening experiments were made to measure the detection thresholds for initial pitch glides in string instrument sounds, where a rapid decline of pitch is caused by tension modulation during the attack. Realistic sounding synthetic tones were generated by additive synthesis. The frequency decay of the glide was defined through the overall decay rate of amplitude, simulating the behavior of real instruments. It was found that on the ERB frequency scale, the thresholds remained roughly constant at approximately 0.1 ERB with varying fundamental frequency. Thus, any pitch glide weaker than the given threshold remains inaudible for most listeners and could be left unimplemented in digital sound synthesis.