The ANR572 Stereo Audio Noise Reduction Processor is an advanced audio noise reduction system based on the proprietary HUSH circuitry that provides a 4 to 1 reduction in noise ( up to 25 dB ) on any noisy audio programming. Radio and TV stations can significantly reduce objectionable noise originating from audio or video tapes, old recordings, telephone call-in lines, ENG Feeds, wireless links and other noisy transmission systems or program sources.
Since this is a single ended noise reduction system, it does not require processing at the program origin. This processor can be used at any point in the audio path that needs noise reduction. The ANR572 can also be used with Dolby B encoded sources with excellent results. It will also pass the SURROUND-SOUND signals for TV stereo. The HUSH process combines a Dynamic Filter and a Downward Expander to provide a high level of noise reduction effectiveness without the sonic artifacts normally associated with other noise reduction systems.
The Adaptive Threshold circuitry detects nominal signal level changes and dynamically adjusts both the Dynamic Filter and Downward Expander thresholds as needed, providing optimal noise reduction regardless of the program source or content. Both Left and Right audio inputs are balanced and high impedance (bridging) or 600 Ohm (field selectable). A front panel input control allows for a wide range of input levels.
A nine segment color LED audio input display is used to set the input control to optimum. The input display is field-selectable for dot or bar-graph mode. Noise Reduction level is indicated by a nine segment color LED display. The display indicates the level of noise reduction being exerted on the audio at all times. It reads from 0dB to 22dB of noise improvement.
The audio outputs are balanced and low impedance to minimize the frequency response roll-off characteristics of twisted pair audio cable. The output level is field selectable to 0dBm, +4dBm, and +8dBm APL (Average Program Level) A front panel switch is available to test the noise reduction system by ear on live program material. This switch makes it easy to do listening tests for proof of performance.