The unit has an adjustable-gain low noise mic preamp with a gain range of +34 to +54 db (or x50 to x500) and provides indication of volume level on digital VU meter on its front panel (to prevent saturation and clipping due to too much gain). The unit accommodates a wide range of microphone types. Phantom power can be inserted by means of a front panel switch. The stereo line input is on a standard 3.5mm (1/8 inch) connector which gets mixed with the amplified microphone signal.
In a typical application a presenter can hookup the audio from their PC to the line input and plug the mic to the XLR. The unit will mix the speakers voice with the PC audio. The HR-101-S has both stereo analog (on 3.5mm) and SPDIF digital (on RCA) outputs as well as a fiber-optic ST connector for driving long cables to 3,280 ft. to compatible receiver.