The LCA 2B is a two channel, all tube unit (except the power supply and sidechain circuit) with an independent compressor and limiter per channel. The VCA (1 dual triode) is placed between the input transformer and the output stage (2 dual triodes.)
The audio signal is picked up after the VCA and fed into the sidechain circuit. The control signal from the compressor and limiter is combined and sent to the link switch, and to the control amp, which feeds the VCA. The two channels of the LCA 2B can be linked together for stereo applications, and also linked to other units via the two link busses.
The compressor has six attack/release presets, based on the Fairchild 670, in addition to manual control. The audio path of the LCA 2B is fully symmetrical from input to output, and both input and output have fully floating transformers. All DC voltages are stabilized except the anode voltage for the output stage.