The RU-MX4 is the ideal choice in many applications where a combination of balanced mic and/or unbalanced line-level signals needs to be mixed. Balanced connections use XLR connectors. Unbalanced signals are coupled through phono jacks. Each of the four inputs can accept either a balanced XLR mic or an unbalanced line-level input. 24 V phantom is individually switch selectable for each mic input. The unbalanced phono jack LINE OUTPUT from one RU-MX4 may connect to the unbalanced input of other equipment, or may be connected to the DIRECT input of another RU-MX4 to expand mixing capabilities. Up to 3 RU-MX4 mixers may be rack mounted in a single rack unit using an RDL RU-RA3HD rack adapter. The RU-MX4 provides one balanced output, switchable for mic or line level. Audio levels are adjustable on the front panel. Each input channel is equipped with a front-panel dual-LED VU meter that follows standard VU ballistics. The final mix is displayed on an LED string VU meter featuring a visually comfortable arc motion. A rear-panel switch allows the soft-knee compressor to be switched in or out. A factory installed output isolation transformer is available by ordering the RU-MX4T.