Stereo frequency EQ, main in/out, tape in/out, L/R phono. Control faders +12db to -12db for 60Hz, 240Hz, 1000Hz, 3500Hz, 10000Hz. Produces fat bass midrange equalization, modified low end EQ for fatter bass.Unit has Class A transistor circuits, uses capacitor, coil inductor circuit design similar to vintage equalizers,tube sound character. #8+ condition