Testing a Modal-analysis-based Model to Predict Averaged Violin Radiation from Mechanical Response Measurements

摘要

A physical Vibration-Radiation (V-R) model was used to predict averaged-over-all-directions pressures entirely from mechanical modal analysis results for a violin. Predictions of the model were compared with the measured averaged pressures obtained with a spherical microphone array from 200 - 1200 Hz. The microphones were mounted inside a small semi-anechoic chamber on a rotatable 30 cm radius semicircle. Acoustic radiation from a violin, suspended in free-free manner from rubber bands, was excited either in a direction parallel to the top plate or perpendicular to the tangent to the bridge at this point by a small force hammer striking the bridge at a common point from the G-string side of the bridge. The V-R model was able to successfully predict both the trends in averaged mode acoustic response for 18 modes below 1.2 kHz and the changes in response associated with changing the excitation direction.