James M. Sabatier
Henry E. Bass
Lee N. Bolen
Univ. of Mississippi, University, MS 38677
A well-controlled low-frequency, high-intensity sound source that is self-contained on a telescoping semi-trailer is described. The three major components of the sound source are: the air-supply system, the Wyle Laboratory air-stream modulator, and the acoustic horn. The modulator has been available for some 20 years and is capable of producing 30 000 acoustic watts of output power from 10 to 630 Hz. It has been modified to allow for CO[sub 2] cooling of the voice coil. The air-supply system consists of a rotary lobe blower driven by a 150 horsepower diesel engine. The acoustic horn is a true 10-Hz exponential horn, 17.1 m (56 ft) long. The mouth and throat diameters are 2.34 m (92 in.) and 0.01 m (4 in.). Measurements of the acoustic output and performance will be presented.