An Experimental Investigation of the Directivity of Violin Sound Radiation

An experimental method for measuring the directivity of violin sound radiation is described, along with detailed derivations of the key mathematical and physical concepts involved. The test violin is mounted on a turntable and excited by a mechanical oscillator at a variety of frequencies. A microphone detects the resulting sound, which is processed using the Fast Fourier Transform to isolate individual frequencies. Measurements are taken at many points around the instrument and graphed on a polar plot to visualize the directivity. Theories as to the possible sources of the directivity are discussed