We want to study auditory masking, the ability of one sound to make another difficult or impossible to hear. By measuring masking using a variety of artificial (e.g., computer generated) signals, we hope to develop an exact quantitative model of auditory processing, that is, we want to simulate the auditory detection mechanism. Of special interest are temporal effects in masking. How does masking vary with the duration of the signal or the interval between the masker and the signal?