Applies to magnetostrictive transducers, of both laminated metal and ferrite types, designed for producing sonic or ultrasonic acoustic power in liquid or solid media, and for different kinds of ultrasonic processing such as cutting, welding, chemical processing, etc. Transducers for information carrying signals are excluded. The transducers, which may be sonic or ultrasonic, operate at the resonance frequency and are supplied from electric power generators. Specifies the essential characteristics and the preferred methods of measurement for evaluating the performance of transducers. Has the status of a technical report.