Purpose: The purpose of this study was to investigate the effects of intelligible and unintelligible primary discourse on acceptance of noise. Of particular interest was the effect of intelligibility on the most comfortable loudness (MCL) component of acceptable noise level (ANL).
Method: ANLs were measured for 30 participants using an intelligible discourse, a reversed discourse, and an unfamiliar primary discourse. For each discourse, MCL and background noise level (BNL) were found. The ANL was then computed by subtracting the mean BNL from the MCL.
Results: The intelligibility of the primary discourse did not affect MCL. The ANL was significantly different for the intelligible versus reversed condition and the intelligible versus unfamiliar (Chinese) condition.
Conclusion: Results indicate that ANL may change as speech intelligibility changes and/or speech recognition ability decreases in adults with normal hearing.