Dynamic range considerations when designing PC sound card based audiometric systems to test human hearing.

An investigation into maximizing the dynamic range of a PC sound card based audiometric test system is presented. Two principle sound paths are characterized: a) the analog line input, and, b) internal waveform conversion from digital formats into analog signals. Each signal path's electrical performance and overall dynamic range is measured using audio harmonic distortion analysis and frequency spectrum analysis tools.

On the synthesis of multiple frequency tone burst stimuli for efficient high frequency auditory brainstem response.

The development and digital waveform synthesis of a multiple-frequency tone-burst (MFTB) stimulus is presented. The stimulus is designed to improve the efficiency of monitoring high-frequency auditory-brainstem-response (ABR) hearing thresholds. The pure-tone-based, fractional-octave-bandwidth MFTB supports frequency selective ABR audiometry with a bandwidth that falls between the conventional click and single-frequency tone-burst stimuli.