Sennheiser's GSX 1000 7.1 USB DAC; audio the way it wants to play - PC Perspective
Sennheiser GSX 1000 Review | headphonecheck.com
Buy EPOS | Sennheiser GSX 1000 Gaming Audio Amplifier / External Sound Card, with 7.1 Surround Sound, Side Tone, Gaming DAC and EQ, Headphone amp Compatible with Windows, Mac, Laptops and Desktops
Amazon.com: Sennheiser GSP 600 USB PC Professional Gaming Headset with GSX 1000 7.1 Surround Sound Gaming Audio Amplifier (PC & Mac), Large Extended Gaming Mouse Pad and Headphone Stand Bundle : Video Games