ASUS Xonar U7 review test and benchmarks. The U7 offers 24-bit/192KHz recording and playback with 114dB SNR, S/PDIF output, 7.1 channel analog output, dedicated stereo headphone output, a volume knob, and it’s all powered of a USB 2.0 port. The headphone output comes with its own DAC and adjustable gain settings, making the U7 capable of driving just about any pair of headphones to ear-splitting levels.

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