How far to trust it
Phone microphones are good in the middle and unreliable at the ends. SoundMess Lab shows you which is which.
Every phone microphone has physical limits. The built-in microphones on iPhone are most accurate between 500 Hz and 8 kHz; outside that range, expect deviations. That is a hardware limit, not an app bug, and SoundMess Lab doesn't hide it.
So the RTA draws each band as bright as it can be trusted: full strength in the middle, fainter towards the bottom and the top. A faint bar is still a real reading. Treat it as a direction, not a number to quote.
| Range | Trust |
|---|---|
| 500 Hz – 8 kHz | High trust |
| 100 – 500 Hz | Medium trust |
| 8 – 16 kHz | Medium trust |
| < 100 Hz | Low trust — for reference only |
16 kHz | Low trust — for reference only |
The info button in the top row (a microphone once audio is running) opens Measurement info. It shows the table above, whether you are in Baseline Mode or Calibrated Mode, and an Audio input card with the microphone in use and its sample rate. Check it whenever you plug in an external microphone, to be sure SoundMess Lab is listening to the one you think.
The device pill on the workbench says which mode you are in:
Baseline: the microphone as it is, with no correction. This is where everyone starts.Calibrated: a compensation curve is being applied, either the built-in one for your model or a file from an external measurement mic. Both are part of Pro, see Calibration.
In Settings → Device, Mode also shows whether a reference-tone trim is on top, for example Baseline + trim.
Related
- CalibrationTrim the level against a 94 dB reference, or load your measurement mic's own calibration file.
- Real-time analyserThe sound split into fractional-octave bands from 20 Hz to 20 kHz, drawn as bars you read from the bottom up.
- QuestionsAccuracy, Pro, recordings and privacy, and what to check when something isn't working.
Still stuck? Write to zhi@nonoaudio.com. Support page