This is a comparison test between WASAPI and standard playback output of the foobar2000 audio player.
Test conditions:
- Windows 7 Pro SP1 x64.
- RightMark Audio Analyzer 6.3.0 (RMAA).
- foobar2000 v1.2.9 (fb2k) with resampling to 96kHz by PPHS plug-in.
- 16bit/44100Hz audio PCM file.
- WASAPI output with 24bit setting of fb2k component.
- MME API output with 100% of volume level and with 24bit/96kHz settings of Windows mixer.
- Input loop of "What U Hear" (WUH) driver of the Creative Sound Blaster X-Fi HD (Digital Music Premium HD) USB sound card with 24bit/96kHz settings.
As you can see the results below, there is no differences. I'm sure that is because of absence of the resampling process by OS due to using of PPHS in according with Windows playback settings. Maybe it would make sense to use an WASAPI component for the fb2k without PPHS plug-in, to bypass a bad- quality resampling of the operating system, if a sound card supports a different sampling frequencies at hardware level (not a X-Fi HD case).
Testing chain: fb2k MME output -> WUH input:
- Frequency response (from 40 Hz to 15 kHz), dB : +0.00, -0.00
- Noise level, dB (A) : -100.5
- Dynamic range, dB (A) : 98.8
- THD, % : 0.0004
- THD + Noise, dB (A) : -92.9
- IMD + Noise, % : 0.0031
- Stereo crosstalk, dB : -99.2
- IMD at 10 kHz, % : 0.0033
Testing chain: fb2k WASAPI output -> WUH input:
- Frequency response (from 40 Hz to 15 kHz), dB : +0.00, -0.00
- Noise level, dB (A) : -100.5
- Dynamic range, dB (A) : 98.8
- THD, % : 0.0004
- THD + Noise, dB (A) : -92.9
- IMD + Noise, % : 0.0031
- Stereo crosstalk, dB : -99.2
- IMD at 10 kHz, % : 0.0033
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| Frequency response |
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| Noise level |
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| Dynamic range |
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| THD + Noise (at -3 dB FS) |
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| Intermodulation distortion |
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| Stereo crosstalk |
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| IMD swept tones |
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| Frequency response swept sine |
fb2k - foobar2000 MME output tests.
fb2kWASAPI - foobar2000 WASAPI output tests.
