RightMark Audio Analyzer - 16-bit 44.1kHz
Moving from subjective listening tests to something more objective, we used RightMark Audio Analyzer to evaluate output quality. We gathered these results with "loopback" tests that route a sound card's output through its line input. We'll kick things off with 16-bit/44.1kHz CD-quality audio.

To keep things simple, I've translated RightMark's word-based quality scale to numbers. Higher scores reflect better audio quality, and the scale tops out at 6, which corresponds to an "Excellent" rating.

RightMark Audio Analyzer audio quality - 16-bit/44.1kHz
Overall score Frequency response Noise level Dynamic range THD THD + Noise IMD + Noise Stereo Crosstalk IMD at 10kHz
ALC889A 4 5 5 5 3 1 3 4 3
Xonar Essence STX 5 6 5 5 6 4 6 6 6
X-Fi Forte 4 5 5 5 3 1 3 6 3

The Essence's signal quality appears to be superior the Forte's with 16-bit/44.1kHz audio. In fact, the Auzentech card doesn't really do anything to differentiate itself from the ALC889A here.

If you want to geek out over a bunch of detailed RMAA graphs, we've provided the raw results for all of our RMAA tests below.

Frequency response

Noise level

Dynamic range

Total harmonic distortion + noise

Intermodulation distortion

Stereo crosstalk