Mic Calibration for Phone-Based Audio Measurement
TL;DR
Phone measurement accuracy depends on calibration. MEMS mics deviate 3-8 dB without it. Use .cal, .frd, or CSV correction files with miniDSP UMIK-1 ($99) or Dayton iMM-6 ($20). With calibration: ±2 dB from 100 Hz-8 kHz.
Why Calibration Is Non-Negotiable
Professional mics: ±1 dB. Phone MEMS: ±8 dB. Calibration removes this uncertainty.
File Formats
.cal: Freq/correction pairs. .frd: Freq, magnitude, phase. CSV: Freq,dB. All auto-detected by SonaVyx.
How SonaVyx Applies Calibration
Interpolated to FFT resolution. Applied before weighting and SPL computation. Affects all tools: SPL, RTA, TF, RT60, STI, problem detection. CAL badge when active.
Recommended Mics
| Mic | Price | Accuracy |
|---|---|---|
| Dayton iMM-6 | ~$20 | ±3 dB |
| miniDSP UMIK-1 | ~$99 | ±1.5 dB |
| miniDSP UMIK-2 | ~$299 | ±1 dB |
Verification
Pistonphone: 94 ±1.5 dB. Or compare with reference on pink noise: ±2 dB. See the phone SPL guide and IEC 61672 guide.
Try It Now
Open this measurement tool in your browser — free, no download required.
Frequently Asked Questions
Last updated: March 19, 2026