| Test | Cowon S9 (2.07, vol 40, no load) | Cowon O2 (1.14b, vol 48, no load) | Cowon D2 (2.57, vol 50, no load) | Cowon X5 (1.10, vol 40, no load) |
| Frequency response (from 40 Hz to 15 kHz), dB: | +0.03, -0.11 | +0.01, -0.05 | +0.02, -0.12 | +0.03, -0.24 |
| Noise level, dB (A): | -91.9 | -92.9 | -92.3 | -92.3 |
| Dynamic range, dB (A): | 91.8 | 92.8 | 92.2 | 92.3 |
| THD, %: | 0.0048 | 0.0099 | 0.0059 | 0.0017 |
| IMD + Noise, %: | 0.0086 | 0.029 | 0.0089 | 0.0069 |
| Stereo crosstalk, dB: | -92.0 | -93.1 | -92.8 | -90.3 |
