Sound power measurements have been widely used as a means of classifying component noise of off-highway equipment. Traditional sound power measurements are accurate and repeatable but require specially designed acoustical rooms. These measurements require removal of the component from the vehicle and a means of powering, loading and monitoring the component.
Sound intensity measurements have been proven as a valuable tool in the calculation of sound power. Measurements can be made directly on the vehicle, thus eliminating the need of external power supplies and loading devices. The sound intensity technique is quick, dependable and does not require the use of special acoustical rooms.
This paper discusses an example of sound intensity for measurement of hydraulic pump noise. These measurements have been verified using conventional sound power measurements on the same pump.