The podDI is a single output summing direct box. * Use it to connect CD and MP3 players, computer sound card outputs, DJ mixers, etc. * to professional equipment with balanced inputs such as a mixing console. * Accepts stereo inputs and sums them into a single mono output.A variable attenuator on each input allows level matching between left and right inputs. * This makes the podDI a passive mixer in split track audio applications, balancing the voice track and the music track levels in the summed mono output.Signal is input via 3.5mm (1/8") stereo TRS jack or color coded RCA phono jacks.