Abstract: Pitch is tracked for a selected source process characterized by a pitch source having many harmonics followed by a bandpass filtering (e.g., human speech or other common processes). The filtering in the original source process causes an original pitch pulse to be seen in somewhat modified form and followed by ringing at band pass filter frequencies. Often, the ringing produces peaks of unpredictable amplitude, a characteristic making it difficult to use simplistic methods such as picking waveform amplitude peaks. The method of the present invention avoids such difficulties by taking into account relative phase of harmonics associated with the basic pitch rate or frequency (F0). Since the bandpass filters in the original process produce ringing in frequencies other than the original fundamental frequency, the instantaneous phase of each of the ringing frequencies are only temporally aligned or lined up well for the duration of the original pitch pulse (i.e.

Abstract: A method and apparatus for improving binaural auditory response for the hearing impaired employs a console in which two microphones are mounted flush with the top surface of the console to eliminate pick up of surface reflections and in which the microphones are spaced to optimize binaural response. The console is adapted to be supported on a table, or the like, to place the microphones closer to the source of sound than is possible with body-attached microphones. Processing circuitry in the console includes two separate signal channels in which the gains are automatically controlled with a common AGC circuit having a fast response section for eliminating sudden noises and a slow response section for controlling the average amplitude level. The fast response section is biased to require a higher level input signal before responding in order to prevent it from cutting off the onset of normal sounds. The AGC circuit is controlled by the channel which receives the higher level signal.