Pressure Chamber Method to Measure Acoustic Impedance in Water

Based on earlier investigations of the pressure chamber method, various chamber set-ups were examined as to their acoustic properties. The main concern of these measurements was to determine the pressure distribution within the chamber, to obtain a suitable crosstalk level, and to extend the frequency range. The investigations resulted in the construction of a pressure chamber which permitted the measurement of acoustic impedances between 120 Hz and 5 kHz.

The reliability of the pressure chamber method was tested with several samples of calculable impedance. Measurement and calculation agreed well.