Paul Kohut

Broadband acoustical transmitting system

An acoustical transmitting system and method for producing a narrow beam of acoustic energy over a broadband operating frequency range utilizes a parabolic reflector dish, a horn-loaded compression driver for directing acoustic energy toward the dishs reflecting surface, and a low frequency driver mounted behind a central aperture in the dish for producing acoustic energy that combines and interacts with the reflected acoustic energy produced by the horn-loaded compression driver. An input signal processing circuit is provided to condition the audio signal to the horn-loaded compression driver and the low frequency driver to achieve on-axis gain and off-axis cancellations at low frequencies. The addition of the low frequency driver to the reflector dish system effectively extends the ability of the system to produce and transmit acoustic energy in a narrow distribution pattern at frequencies below 1000 Hz using a four foot diameter dish.

Method and circuit for improving the polar response of a two-way horn-loaded loudspeaker system

A method and correction circuit for improving and controlling the listening window and response of a two-way loudspeaker system utilizing a horn-loaded high frequency driver. The correction circuit includes adjustable active all-pass and band-pass filters, in a specific arrangement, coupled with conventional cross-over filters to achieve a maximally flat amplitude and phase response acoustically throughout a preferred listening window. A spectrum analyzer measures the near-field responses of the individual and combined transducers while adjustments are made. A phase shifting circuit is included in the low frequency channel which results in improved near-field to far-field response consistency and significantly improves the subjective characteristics of the high frequency horn.