HP12E is a professional 8-channel headphone amplifier. The front panel has eight stereo 6.3 output ports, with a separate volume control knob for each channel. Besides, the front panel has one aux input for every two channels, and a control knob allows you to change how much the main and auxiliary inputs mix together. The stereo/mono switch converts the stereo output of the headphones to L+R mono. In addition, each of the two channels has an 8-segment LED indication to show the strength of the signal; the level switch button allows you to switch between each channel’s display. The main input ports include XLR and 6.3 balanced ports. Additionally, it offers a single serial input port for connecting several HP12Es in series.