The Palmer Monicon L is a precise analog volume control that connects between computers or audio interfaces and self-powered monitor loudspeakers. To prevent signal coloration the circuitry is all passive, the LED indicators and built-in headphone amplifier are powered by the included DC adapter.

The Monicon L's stereo input is on balanced combo sockets, the AUX input features a 3.5 mm TRS jack and RCA connectors. The compact console sports dual outputs for two pairs of monitor speakers and a summed mono output on XLR connectors. The stereo and AUX inputs are alternatively selectable, the outputs can be activated individually and in tandem. Besides the large stereo volume knob the Monicon L provides mono, mute and PFL switches, a 6.35 mm TRS headphone jack as well as separate AUX and headphone level controls for additional convenience.