The present invention, generally speaking, picks up a voice or other sound
signal of interest and creates a higher voice-to-background-noise ratio
in the output signal so that a user enjoys higher intelligibility of the
voice signal. In particular, beamforming techniques are used to provide
optimized signals to the user for further increasing the understanding of
speech in noisy environments and for reducing user listening fatigue. In
one embodiment, signal-to-noise performance is optimized even if some of
the binaural cues are sacrificed. In this embodiment, an optimum mix
ratio or weighting ratio is determined in accordance with the ratio of
noise power in the binaural signals. Enhancement circuitry is easily
implemented in either analog or digital form and is compatible with
existing sound processing methods, e.g., noise reduction algorithms and
compression/expansion processing. The sound enhancement approach is
compatible with, and additive to, any microphone directionality or noise
canceling technology.