Effects of Intensity and Age on Perception of Accent in Isochronous Sequences of a Snare Drum Timbre

Musical expression is often dependent upon accentuation, yet there is little research in the perception of dynamic accent in music and its relationship to intensity just noticeable differences (JNDs). This experiment estimated relationships among (a) accent limen (AL), (b) difference limen (DL), and (c) the ages of the nonmusician female subjects (N = 51). The AL was the intensity increment producing 80% correct criteria in subjects' perceptions of single accented tones embedded within seven-tone isochronous series. The unaccented tones were identical-timbre 87-dB(A) digitally produced snare drum sounds. The DL was the intensity difference in tone pairs that produced a 75% correct criterion. The relationship between AL and DL was not significant [F(1, 48) = 5.505, p = .197]. The relationship between AL and age was significant [F1, 48) = 5.732, p = .021], suggesting that the amount of intensity change required for perception of intensity accentuation in musical settings (especially by children) should be larger than the DL.