It is recommended to use a USB device rather than a sound card with the Sennheiser headset.  This is because the optimum signal from the Sennheiser microphone may be compromised when passing through a poor sound card.

If it is desired to connect it directly to the computer's sound card, the Andrea APS- 100 battery box is necessary when connecting to a Creative SoundBlaster Live or Audigy sound card and compatible cards (SoundMax, Realtek AC97, SigmaTel, etc). It serves as an auxiliary power supply. This unit supplies a small voltage which is needed to drive the electret microphone element. The wiring of some microphone plugs enable this voltage to be pulled directly from the soundcard or USB Pod. Others like the Andrea ANC range and this microphone require the APS-100 battery box to drive the electret elements.

2 AAA batteries last approximately 3 months.

The Andrea Black Power converter (P-100) is required for compatibility with Full Duplex USB devices such as the Buddy USB 5G and the VXi Full Duplex (Two-Way) sound devices.