Abstract:
The sound intensity patterns of two G1 handbells were investigated. One bell is aluminum and the other is traditional bronze. The results indicate that the aluminum bell has a better radiation efficiency for the (2,0) mode fundamental (f=49 Hz). Sound intensity was mapped for the two tuned modes of vibration: the (2,0) and (3,0) modes. The parametric radiation (twice the mode frequency) was significant for both modes, especially the (3,0). The measurement of both active and reactive sound intensity reveals a better picture of the sound field than sound pressure alone. Both of the bells are poor radiators of the fundamental because of their small dimensions compared to the sound wavelength in air. [Both bells on loan from Malmark, Inc.]