I am using a USB sound card for measurements. It's a pain, but I have nothing better yet.
The sound card is the E-MU 0204
. I've chosen it for the specs:
- Dynamic Range (A-weighted, 1kHz, min gain): 113dB
- Signal-to-Noise Ratio (A-weighted, min gain): 113dB
- THD+N (1kHz at - 1dBFS, min gain): -101.9dB (.0008%)
The sound card is intefaced to the real world by Pete Millett's sound card interface
The software is SpectraPLUS 5.0 by Pioneer Hill Software (PHS). (No link because my antivirus says their web site is infected.) The software runs on an old MacBook running Windows 7 in Boot Camp.
The results do not seem to be affected by nearby computers, flurescent lights, switching power supplies, etc.
The results are affected by:
- Windows Mixer settings (levels and sampling rates)
- Software settings (levels and sample rate)
- Grounding of the sound card, the interface, and the device under test
The greatest source of pain is...