The FP-ALC2 is a great piece of equipment for cleverly controlling the audio levels of consumer devices which have fluctuating audio output levels. This two channel module incorporates phono jack inputs and outputs. You can feed a variety of audio devices into it, such as satellite receivers and multiple CD changers. These kinds of devices have variable audio outputs, requiring constant adjustments to be made by the user. The FP-ALC2 takes away all that hassle and does it for you, without you even noticing. Simply set the gain adjustment as high as possible with the loudest audio source, without the 'input overload' indicator flashing, and the module does the rest. It really is that simple! A consistent -10dBV output level is maintained for input signal variations as large as 25 dB ensuring a comfortably conformable listening experience!