With a slim 2HP, the Instruo 1[f] has a lot to offer. If audio signals or control voltages are present at both inputs 1 and 2, they can be mixed and crossfaded like on a DJ mixer (crossfader). If a signal is present at only the first input, the fader acts as an attenuator. If no input is connected, the module functions as a manual control voltage source with a range of ±10 volts.