Fundamentals of Acoustics

In both wire and radio telephony speech, music, and hearing are involved. The speech sounds containing the information to be transmitted often originate in enclosed spaces such as rooms, telephone booths, and radio studios. The acoustical characteristics of these enclosed spaces may influence greatly the speech sounds that operate a telephone transmitter or a radio microphone.

Transmitters and microphones must create electric signals that vary in accordance with the sounds to be transmitted. At the distant receiving station, the electric signals are reconverted to sound waves. Before transmitters, microphones, receivers, and loudspeakers can be considered, acoustics and the nature of the process of speaking and hearing must be understood.