Controlling the shape of an acoustic spectrum automatically in various spaces

Abstract

Often, when a room is excited by a specified spectrum, the resulting spectrum differs in shape from that desired. Caused by the impedance of the space and by the objects within, in the past, the change has been accounted for by the use of a spectrum shaper before the noise generator, which was manually adjusted so that the desired shape and level of the output was achieved. This paper presents a discussion of a bus-controlled spectrum shaper that, in conjunction with a computer controlled realtime analyzer, allows the shape of the desired spectrum to be achieved without operator intervention. Uses for vibration excitation will also be discussed.