For connection of film projectors, tape recorders and phonographs to standard Low-Z balanced microphone input of public address system. RCA, 1/4" (6.35mm) and mini-jack inputs; unbalanced 1/4" (6.35mm) line output; switches for high/low level attenuation 16 Ohm load, and ground lift; also male XLR-type balanced output. Uses DBT-1 transformer (20K/150 Ohms).