Just noticeable differences in sound intensity of piano tones in non-musicians and experienced pianists

Abstract

Changes in sound intensity are important components of piano performance. Previous research in this area has largely focused on perception of changes in pitch and timing, with little investigation of sound intensity. The present study used Musical Instrument Digital Interface (MIDI) technology to algorithmically control the key velocity, and thereby sound intensity, of consecutive piano tones. Non-musicians ( n = 20) and experienced pianists ( n = 30) played pairs of consecutive piano tones with 0–15 arbitrary units (a.u.) of change in key velocity, indicating whether they perceived the first, second, or neither tone as louder. All participants completed the test with C4, and a subset ( n = 24) with pitches C2 and C6 also. The mean just noticeable difference (JND) ranged from 2.71 to 4.48 a.u., corresponding to 0.68–1.22 dBC on the Yamaha Disklavier used to produce the stimuli. Experienced pianists demonstrated lower JND, which the authors theorize may be linked to listener motivation. When two tones were played with the same key velocity, participants tended to perceive the first tone as louder. The authors discuss a number of factors that may be relevant considerations for application of the findings in music and psychoacoustics research. These findings hold insight for music performance researchers, psychoacoustics researchers, and pedagogues.