The ANG-2200 is designed to create a perimeter of noise around a target area that defeats wired microphones inside walls, contact microphones, audio transmitters located in AC outlets, and laser/microwave reflections from windows. Most sound masking systems inject noise into an otherwise benign environment. In this environment, the occupants must raise their voices above the noise level to communicate, which invariably, eliminates the benefit of noise masking. REI's masking system injects noise into the environment perimeter and not directly into the environment. This approach allows normal conversation while defeating eavesdropping devices that rely on acoustic leakage. Features The ANG-2200 offers two channels each with a truely random noise source. Both channels have a seperate high and low frequency control in order to compensate for loses found in the enviroments material composition. The REI noise masking system consist of a main unit (the ANG-2200) and three optional accessories that are purchased to tailor the system to the environment of concern. The ANG-2200 accessories are: TRN-2000 Transducer used to inject acoustic noise into walls, ceilings, windows, plumbing, and air ducts. OMS-2000 Omnidirectional Speaker used to project acoustic noise into drop ceiling air spaces, closets, crawl spaces, and air ducts. EAR-200 Electro-Acoustic Receiver used to evaluate the level of audio leakage and set the specific masking level. ANG-2200 Advantages 2 seperate channels Truly random noise sources High Frequency and Low Frequency Controls Overload Protection Specifications Size: 1.6 x 5.5 x 8 in. (4.1 x 14.0 x 20.3 cm.) Weight: 1.2 lb. (.5 Kg) Output Max: 10 V p-p @ 6 ohms Min. Load: 2 ohms Frequency: 125 Hz – 4 kHz Power: 12Vdc, 1A