Decibel notation with correlated and uncorrelated signals.

Audiologists perform sound level measurements in a variety of settings. These measurements typically involve clinical audiometric calibration, specification of sound field levels in industrial environments, psychoacoustic experimentation, or specification of sound levels in hearing and test boxes or anechoic chambers. Any of these circumstances can present problem situations in which some form of signal combination is involved. Solutions of such problems require use of the concepts of average power and signal correlation, as they are related to decibel notation. These concepts are discussed in the present paper, and several examples that apply these concepts to specific measurement situations are presented.