Effect of a Reflecting Plane on the Power Output of Sound Sources

The presence of a reflecting plane boundary will affect the power output of a sound source located above it. This effect may be expressed as a “power amplification factor” which has been calculated for a number of elementary sound sources (monopole, dipole and longitudinal quadrupole) as a function of the distance between the plane and the source. Special attention has been given to evaluation of the source height yielding minimum power output and to the ratio between the maximum and minimum power radiated.