The Numark DM-500 DJ Mixer is a vintage stereo studio pre-amplifier designed for tabletop use. It has four buses, analog input/output ports, and a range of features including talkover, line/phono switch, and equalizer. The mixer also has a delay effect/enhancement and is made in Japan. It comes in black and is sold as a unit. One of the switches has broken off. See close up in pics
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