Performance of dual-microphone in-the-ear hearing aids

Fifty subjects with mild to moderate-severe sensorineural hearing loss and prior experience with binaural amplification were evaluated at two sites (25 subjects at each site). Signal-to-noise ratios (SNRs) were measured using the Hearing in Noise Test (HINT) after each subject wore binaural in-the-ear hearing aids programmed for omnidirectional and dual-microphone performance, for 4 weeks. Both microphone conditions were evaluated under "ideal" (signal at 0 degrees; noise at 180 degrees) and "diffuse" (signal at 0 degrees; correlated noise at 45 , 135 degrees, 225 degrees, and 315 degrees) listening conditions. Results revealed statistically significant mean improvements in SNRs between 3.7 and 3.5 dB at Site I and 3.2 and 2.7 dB at Site II for the ideal and diffuse listening conditions, respectively, for the dual-microphones in comparison to the performance provided by the omnidirectional microphone.