We postulate that measurement precision and the magnitude of acoustic emission signals will be affected by the type and thickness of the couplant used to couple the transducer to a structure. A theoretical solution is provided to determine the transmission coefficient of a multilayer system of n layers. A longitudinal wave is assumed to be normally incident on the system. Theoretical transmission coefficients are obtained for waves transmitted through three, four, and five layers. Specific calculations are carried out for a particular five-layer system which is applicable to an acoustic emission transducer. Conclusions are drawn concerning the measurement precision likely to be obtained from this type of transducer used in this configuration.