These anachronistic line level Purist Mixers were intended to be used in pairs (or more) for 10 into 2 stereo mixing in the field or in the control room. Two versions were available: with or without internal mic preamps. The version without mic preamps was optimised for use with our Manley 40dB mic preamps. Panning from a mono source could be achieved by simultaneously driving two inputs (with a Y-connector) or by patching a jumper between the paralleled RCA input connectors provided on the back. 

The actual mixing was achieved actively by each input having its own dedicated input grid; not by the conventional potentiometer-and-build-out-resistor method which causes great insertion loss requiring large amounts of makeup gain which unnecessarily might increase the noise-floor. 

The 4-microphone input version offered identical features in a slightly deeper 1u case plus 1 line input as above described. Phantom voltage was included and the mic gain was set for 45 dB (plus 15 dB in the mixing stages). In the interest of lowest possible noise-level, the "Purist Mic Mixer" utilized a separate outboard dual-mono power supply.