MEASUREMENT OF PERSTIMULATORY LOUDNESS ADAPTATION

Experiments were conducted to investigate two of the variables encountered in the measurement of perstimulatory loudness adaptation. The first of these variables is the instruction to the observer for comparing the sensations in the test and control ears; i.e., equality based on equal loudness versus that based on a midline localization of the sound image. The second is the time of presentation of the comparison tone; i.e., simultaneous presentation with a portion of the adapting tone versus a delayed presentation mode in which the comparison tone occurs after the termination of the adapting tone. The results reveal (1) that adaptation measured by localization balances exceeds that measured by loudness balances and (2) that the simultaneous loudness†balance method shows more apparent adaptation than the delayed balance method. Hypotheses are presented in an attempt to explain these results. © 1968, Acoustical Society of America. All rights reserved.