Sennheiser's GSX 1000 is an external USB 24-bit/96 kHz DAC, using Sennheiser's own 7.1 Binaural Rendering Engine with a headphone amp and a line-out port to connect to active speakers. The only difference between the GSX 1000 and the 1200 is that you will not be able to daisy chain multiple DACs together, a feature not many of us need.  TechPowerUp were more than impressed with the sound, but the DAC fell short of perfection as you cannot modify the preset equalizer choices nor disable the noise cancellation on the mic jack; both of which should be possible on an audio device of this price.

"The Sennheiser GSX 1000 Audio Amplifier is a beautiful external USB sound card equipped with the best 7.1 virtual surround sound system we've heard so far, and a host of other interesting features primarily aimed towards hardcore gaming."

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