Experimental investigation of the effects of extra mass on a piano soundboard’s vibration property
Hao Xing, Bonan Zhao, Haiyan Y. Zhao · The Journal of the Acoustical Society of America · 2007
A soundboard, as an important resonance component of a piano has been continuously studied in the past several decades. It is known that the variation of mass distribution on a soundboard could affect its vibration properties and the sound quality of a piano. However, those effects have been seldom investigated until now. In this paper, an experiment is carried out to study the effects of additional mass-blocks on a soundboard. Small pieces of metal blocks are pasted on several different locations on a soundboard, and a laser vibrometer is used to extract its mode shapes and spectrum under the excitation of an acoustic source with frequency ranges from 10 Hz to 1 kHz. The results show a notable difference of spectrum between mass-added cases and original in low frequencies, but little difference in high frequencies. It could be concluded that additional mass-block could greatly affect the energy of the low-mode of a soundboard.