Support

The meter shows "Microphone off"

Decibelwerk needs the microphone to read the level. Open Settings › Apps › Decibelwerk and turn on Microphone. The app never records or uploads sound; it only reads how loud it is.

How accurate is it?

Decibelwerk reads the microphone in iOS measurement mode, so the phone doesn't boost quiet sounds. In ordinary rooms readings are usually within a few dB; below about 35 dB and above about 110 dB a phone microphone is less reliable. Take the case off, keep the bottom microphone uncovered and hold the phone still. More in how to measure decibels on iPhone.

Calibrating against another meter

With Pro, the CAL knob on the meter trims readings by up to 10 dB either way in 0.5 dB steps. Put both meters side by side with a steady sound and turn CAL until they agree.

My noise log stopped

Keep Decibelwerk open on screen while a log runs. iOS pauses the microphone when an app goes into the background. Logs stop on their own after 8 hours.

The speaker still sounds muffled

Run the speaker cleaner again after a minute's rest, then leave the iPhone somewhere dry with moving air. Apple's advice for a wet iPhone is in this guide. If it's still muffled after a day, contact Apple Support.

Restore a purchase

Open the app, tap PRO, then Restore. Use the same Apple ID you bought with.

Still stuck?

Email info@decibelwerk.com with your iPhone model and iOS version.