Duration Sensation When Listening to Pure Tone and Complex Tone
Kazi Saifuddin, Takaji Matsushima and Yoichi Ando

The duration sensation (DS) is a primary sensation of the sound stimuli of complex-tone, because musical notes include information of pitch and duration as well as loudness. Paired-comparison tests while changing the residue pitch or fundamental frequency, which correspond to the delay time of the first peak (t₁) extracted from the autocorrelation function (ACF) were conducted. In Experiment 1, the white noise was used as a reference, and complex-tones (two pure-tone components) with three fundamental frequencies (250, 500, and 1000 Hz) were used as the test stimuli. Ten subjects judged whether or not the white-noise duration was longer than the complex-tone duration. Throughout investigation, the sound pressure level was fixed at 80 dB(A). And, the rise and fall times, defined as the time at a -3 dB drop from the steady level were kept a constant 1 ms. Results show that the DS of pure-tone and bandpass-noise stimuli is judged to be longer when is longer t₁. Results of experiment 2 show that the DS of complex-tone stimuli is the same as that of the pure tone, if values of t₁ are the same.

Key words: duration sensation, autocorrelation function (ACF), pure tone, complex tone