Apparatus for Outdoor Testing of Sound Signals

摘要

Two techniques for improving the outdoor testing of sound signals were investigated. With the signal and microphone mounted 47 feet above ground, the effect of using a directional microphone to reduce the reflected sound was determined. The report concluded the directional microphone offers definite advantages in outdoor testing. The use of a fast response oscillograph for discriminating between direct and reflected sound was also investigated. The slow rise time of the signal under test made this method impractical in correcting for reflections. (Author)