Decibel meter A+ - App Support

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Decibel meter A+

App Support & User Guide

About Decibel meter A+

Decibel meter A+ is a noise measurement app that uses the iPhone's built-in microphone to measure environmental sound levels in decibels (dB).

The app can be used to check everyday environmental noise, including surrounding noise and possible floor or neighbor noise.

Decibel meter A+ does not require an account or login.

🎬 Video

Main Features

🔊 Noise Measurement

Measure surrounding sound levels using the iPhone's built-in microphone and view the measured level in decibels (dB).

🎙️ Noise Recording

Record environmental noise using the iPhone's microphone. Recorded audio is stored inside the app and can be played back later.

📊 Decibel Data

During recording, the app measures decibel levels 10 times per second and saves the corresponding measurement data as a text file.

📁 Archive

Store recorded audio and corresponding decibel measurement data inside the app. You can play recordings and export files externally.

✂️ Trim

Extract only the loud sections of a losslessly recorded audio file that exceed a selected decibel threshold.

📂 Grouping

Group noise measurement files by minute to make it easier to identify noise events, listen to recordings, and export data.

Basic Noise Measurement

For the initial setup, use the app in a quiet environment.

1. Close the door and prepare a quiet room.
2. Press the Record button to start measuring.
3. Check the dB value displayed on the gauge.
4. In a very quiet environment, adjust the reading to 26 dB.
5. If the reading is above or below 26 dB, use the Up (▲) or Down (▼) button to adjust it to 26 dB.
6. Once the adjustment is complete, begin measuring environmental noise.

Why 26 dB?
The app uses 26 dB as a baseline reference for a quiet-room environment. Adjusting the initial reading according to the environment can help provide more consistent measurements.

Calibration

C Button — Calibration Window

Tap the C button to open or hide the calibration window. The calibration controls allow you to adjust the initial measurement level.

Calibration Procedure

1. Move to a quiet, enclosed environment.
2. Close the door and minimize surrounding noise.
3. Start recording.
4. Use the Up (▲) and Down (▼) buttons to adjust the gauge to 26.0 dB.
5. Use the calibration controls to set the initial reference level.
6. Begin measuring environmental noise.

Controls

26 Button

Toggles the decibel display.

C Button

Toggles the calibration window.

Record Button

Tap the Record button to start or stop recording environmental noise.

Up (▲) Button

Increases the calibration level.

Down (▼) Button

Decreases the calibration level.

Gauge Screen

The gauge screen provides a visual display of the measured noise level.

Swipe Left

Swipe left to hide the gauge screen.

Swipe Right

Swipe right to show the gauge screen.

Decibel Information & Recordings

Doc Button

The Doc button allows you to view decibel information measured over time.

Decibel levels are recorded 10 times per second, allowing you to review fluctuations in noise levels.

You can also listen to the corresponding recorded audio.

Archive

Recording Files & Text Files

Recorded audio and corresponding decibel data can be stored inside the app.

Decibel measurement data is saved in text file format.

Playing and Exporting Files

Tap a recording to play it. Use the Export button to share recorded audio or measurement data externally.

Grouping

The Grouping button organizes measurement files by minute. This makes it easier to find specific noise events, listen to recordings, and export data.

Trim — Extract Loud Sounds

The Trim feature allows you to extract only the loud sections of a losslessly recorded audio file.

Set a decibel (dB) threshold, and the app identifies sections where the recorded sound exceeds that level.

The selected sections are extracted and saved as a shorter audio file.

Frequently Asked Questions

Do I need to create an account?

No. Decibel meter A+ does not require registration, an account, or login.

Where are my recordings stored?

Recorded audio files are stored inside the app.

Where is my decibel measurement data stored?

Measurement data is stored inside the app. Decibel measurements can also be saved as text files.

Can I listen to the recorded noise?

Yes. You can play recorded audio from the Archive and Doc sections of the app.

Can I export my recordings?

Yes. Use the Export button to share recorded audio or measurement data externally.

How often is the decibel level measured?

During recording, the app measures and records decibel levels 10 times per second.

Can I measure floor or neighbor noise?

Yes. The app can be used to monitor environmental noise, including sounds that may be perceived as floor or neighbor noise.

However, measurements made with an iPhone microphone may differ from measurements made with professional sound-level meters.

For official, legal, or professional noise assessments, use appropriate professional measurement equipment or consult a qualified professional.

Why is my measured dB value different from another sound meter?

Measurement results can vary depending on:

• The iPhone model and microphone characteristics
• The measurement environment
• The position and orientation of the iPhone
• Background noise
• Environmental conditions
• Calibration settings

What does the 26 dB setting mean?

26 dB is used as the app's baseline reference for a quiet-room environment.

What should I do if the microphone does not work?

Check that microphone access is enabled for Decibel meter A+.

On your iPhone, go to:

Settings → Privacy & Security → Microphone

and make sure microphone access is enabled for Decibel meter A+.

Do I need to delete an account?

No. The app does not use user accounts, so there is no account deletion or withdrawal procedure.

In-App Purchases

Decibel meter A+ does not offer subscriptions. The following optional in-app purchases are available:

Remove Ads — $0.99

Remove ads within the app.

Coffee for App Developers — $0.99

Send the developer a cup of coffee as a gift.

Coffee & Cake for the Developer — $2.99

Treat the developer to coffee and cake. Thanks!

All purchases are optional. There is no recurring subscription.

Privacy

Decibel meter A+ does not require an account or login. Recorded audio and noise measurement data are stored locally within the app.

The app uses the iPhone microphone for noise measurement and audio recording.

For complete information about data handling, advertising, microphone access, and privacy choices, please review our Privacy Policy.

View Privacy Policy

Contact Support

If you have questions, encounter a problem, or have suggestions about Decibel meter A+, please contact us.

Email: boyoung1977@gmail.com

When contacting support, please include:

• A description of the problem
• The steps that caused the problem
• Your iPhone model
• Your iOS version
• A screenshot, if applicable

Important Notice

Decibel meter A+ uses the iPhone's built-in microphone to estimate environmental sound levels.

Measurement results may vary depending on the device, microphone characteristics, calibration, and measurement environment.

The measurement results are provided for reference purposes and should not be considered a substitute for measurements performed using professional sound-level measurement equipment.

For legal, official, or professional noise assessments, please use appropriate professional equipment or consult a qualified measurement professional.

Video tutorial

Guarda il video per vedere come utilizzare Decibel meter A+ e scoprire le principali funzioni dell'applicazione.

Guarda il video su YouTube

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Decibel meter A+ — App Support