Abstract:
In this Technical Note different ways for the determination of eigenmodes of a flue organ pipe are presented. Finite element calculations on a model of the pipe are compared to measurements using force excitation with a shaker and sound pressure and velocity measurements with subsequent modal analysis. Variation of damping is used to identify structural modes and air column modes in a limited frequency range. In an accompanying paper in this issue of ACUSTICA - acta acustica, microphone recordings of the blown flue organ pipe are presented that indicate an influence of structural eigenmodes of the pipe on the transient sound.