2015 年 17 巻 1 号 p. 53-62
The design principle of Tangible User Interfaces has been applied to musical interfaces in order to realize more accessible usage of computers for musical expression. In this paper, we propose DropNotes, a tangible tabletop user interface, that enables intuitive sound source sampling and audio processing. DropNotes is comprised of colored water, bottles, a dropper, a funnel and a glass table. Users instill a sound source into colored water in a bottle and put its droplets onto a glass table to playback the recorded sound. The composition of droplets determines pitch, volume and sequence of allocated sounds. Users accomplish the complicated task of recording and arranging music by manipulating familiar tangible artifacts. The paper also reports the results of a usability test that compared DropNotes to a prevalent digital audio workstation in order to validate the concept. The results indicate that DropNotes allows users to more readily sample a sound source and that even novices can intuitively compose music.