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ETS VNF-4 4 Channel Voice Notch Filter Microphone Interface For Less Background Noise
The ETS VNF-4 is a four channel, low cost background noise reduction module for use with ETS microphones and a DVR, I/P camera, etc. It provides a boost of frequencies in the human voice band (1.7Khz) and 10db per octave attenuation on both sides of the band pass. The result is significantly reduced background noise and increased intelligibility of speech.
Additional features include adjustable output levels, euro-style connectors, and it is reverse polarity protected and fused.