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Volume 113, Issue 6, June 2003
- ACOUSTICAL MEASUREMENTS AND INSTRUMENTATION 
113(2003); http://dx.doi.org/10.1121/1.1572140View Description Hide Description
A water-filled impedance tube capable of improved measurement accuracy and precision is reported. The measurement instrument employs a variation of the standardized two-sensor transfer function technique. Performance improvements were achieved through minimization of elasticwaveguideeffects and through the use of sound-hard wall-mounted acoustic pressuresensors.Acoustic propagation inside the water-filled impedance tube was found to be well described by a plane wavemodel, which is a necessary condition for the technique. Measurements of the impedance of a pressure-release terminated transmission line, and the reflection coefficient from a water/air interface, were used to verify the system.