Abstract: A method and apparatus for increasing perceived reverberant field diffusion in systems providing electro-acoustic reverberant enhancement to rooms or spaces includes independent modulation of the phase of each individual release loudspeaker channel in response to an effectively random infrasonic modulating signal, independently developed for each channel. Each loudspeaker release channel is fed from an electronic reverberator. The release channel signals are timed to emerge into the room at different times. The amplitude of each channel may also be modulated. In one embodiment, independent devices for generating infrasonic modulating signals have the characteristics of at least two frequencies being present within the range of about five seconds/cycle to about five cycles/second, for supplying control signals for achieving modulation in phase and amplitude.

Abstract: A search mount for a telescope and a method of operation in which a telescope mount is provided which is indexable about a vertical axis and also about a horizontal axis so as to lay the telescope in any desired direction. The mount is provided with motors, and the movement of the motors is under the control of digital circuitry, and manual switches. The drives between the motors in the telescope mount embody backlash free reduction gearing of novel design and construction. In particular, the motors operate without requiring any feedback to effect control thereof.