Date of Award

Spring 2010

Document Type


Degree Name

Doctor of Audiology (AuD)


School of Communication

First Advisor

Melinda F. Bryan


The present study investigated the effects of asymmetric directional microphone fittings (i.e., an omnidirectional microphone on one ear and a directional microphone on the other) on speech understanding in noise and acceptance of background noise in 15 full-time hearing aid users. Subjects were fitted binaurally with four directional microphone conditions (i.e., binaural omnidirectional, asymmetric right directional, asymmetric left directional and binaural directional microphones) using Siemens Intuis directional behind-the-ear hearing aids and comply earmolds. The results revealed that speech understanding in noise improved when using asymmetric directional microphones compared to binaural omnidirectional microphone fittings and were not significantly hindered compared to binaural directional microphone fittings. The results also revealed that listeners who wore asymmetric directional microphones were more likely to accept background noise (i.e., accept hearing aids) than listeners fitted with binaural omnidirectional microphones. Lastly, the results revealed that the ANLs were better for the binaural directional microphones when compared to the asymmetric directional microphones, maximizing listeners' willingness to wear hearing aids in the presence of noise.