Procedure for calculating fluctuation strength for marimba tremolo

抄録

Our previous study described a procedure for calculating fluctuation strength (FS) from tremolo produced with a mandolin. However, the forms of the amplitude envelope on sounds played on the mandolin vary so little that how the forms affect the perception of fluctuation has not yet been investigated. Therefore, we present a procedure for calculating FS by considering the form of the amplitude envelope on a tremolo produced with a marimba, whose forms of the acoustic waveform on the tremolo vary due to the stiffness of the head of the mallet. We obtained acoustic features of a marimba tremolo as a set of parameters and calculated FS using the parameters. We found that the procedure observing three features concerning constant fluctuation, the deviation for time and amplitude, and deformation on the envelope can calculate FS correctly.