Power amplifiers for underwater transducers

Underwater transducers differ from loudspeakers in that they generally present a highly reactive load impedance, and may be subject to arcing. Conventional Hi-Fi amplifiers are not effective in driving reactive loads and do not afford the necessary protection. This paper discusses Class S, Class D, and Linear power amplifiers giving the features and limitations of each. Transient ringing with voltage and current sources is discussed. The simultaneous transmission of two or more frequencies or of noise requires substantial derating of an amplifier. Several special cases and their applications are discussed.