The Audio Developments AD144 12x4 Input/Output VU Studio/O.B. Mixer has Mic/Line and Stereo Line Input module options. Each input has a three band equalizer; phase switch; separate routing switches for the four main groups; PFL, monitor mix and solo in place; plus an overload indicator. Twelve to twenty-four input chassis are available. The four master outputs controlled by individual main output faders. The outputs are transformer balanced on XLR connectors and have switchable, stereo linkable limiters; and an LED indicating the action of limiting. The four independent auxiliary sends from each input with separate level controls and on/off, pre/post switching to separate mix busses. The outputs are transformer balanced on XLR connectors and controlled by rotary master potentiometers. The comprehensive M-S stereo facilities on the inputs, outputs and monitor chain allow decoding from M-S to L-R and L-R to M-S. It features four electronically balanced line level returns on jacks enable monitoring of mono or stereo sources from such as tape recorders.
The two monitor modules allow separate control of left and right. Monitor 1 is transformer balanced on XLRs and can be switched between all the main outputs, with PFL capable of being mixed in. And monitor 2 is the headphone output and follows monitor 1 except that PFL selection automatically overrides other selections. An M-S matrix amplifier may be inserted in the monitor path in order to decode a main output in the M-S domain or check mono compatibility and phase cancellation when in the L-R domain. All input and output connectors are presented on one surface of the case and in line with their corresponding modules. The mixer receives its power from an external DC voltage source. It features 15 way D connector for feeding external equipment.