Vibrational analysis of glass harp and its tone control

• Published in: Acoustical Science and Technology Vol. 28; no. 6; pp. 424 - 430
• Main Authors: Uchida, Koichi, Kishi, Kenshi
• Format: Journal Article
• Language: English
• Published: Tokyo ACOUSTICAL SOCIETY OF JAPAN 01.01.2007; Acoustical Society of Japan; Japan Science and Technology Agency
• Subjects: Acoustics; Exact sciences and technology; Finite element method; Fundamental areas of phenomenology (including applications); Glass harmonica; Glass harp; Music and musical intruments; Physics; Pitch tuning; Solid mechanics; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Wineglass; Vibration; Glass; Timbre; Modeling; Tuning; Glass harmonica; Finite element method; Cutting; Wineglass; Hearing; Musical acoustics; Glass harp; Pitch(acoustics); Structural analysis; Musical instrument; Production process; Finite element method. Pitch tuning; 43.75.Kk
• ISSN: 1346-3969; 1347-5177
• DOI: 10.1250/ast.28.424

In this paper, we focus on the control of the tone of a glass harp during the process of manufacturing, and on the analysis of the vibration of the glass harp using a finite element method. First, the effect of various factors on results is studied, such as the element type that enables a good geometries approximation and the number of divisions on the accuracy of mode frequencies. Second, we examine how each mode frequency changes with the bulge of the glass harp. The results demonstrate that the use of a bulge is effective in controlling the pitch and the timbre. Third, the pitch can be varied over a wide range by changing the bulge of the cup. In particular, it can be finely adjusted by cutting the inside bottom of the cup so as to form of a small circular groove instead of using a conventional method, which involves cutting the outside of the cup.