The APS-100 is a battery box (uses 2 AAA batteries – not included) to power the electret element in microphones. High quality electrets microphones (such as the KnowBrainer Hands-Free Headset, the Sennheiser ME3, and various ANC microphones) place a power demand on sound cards. Typically the sound card in the computer will provide the necessary power, but some cards fail to provide the necessary power through the “Mic” port to power electret microphones (e.g. older IBM Thinkpads).


