Sound Level Analyzer Lite


"Sound Level Analyzer Lite" is a sound level meter app for iPhone. It is a free app that has simplified the function of "Sound Level Analyzer".

Available in variety of applications as the neighboring environmental noise measurement, audio system check, vehicle interior noise check, sound check of live events, and more.

This app can easily set the frequency weighting characteristic and the time weighting characteristic necessary for sound level meter, and appropriate sound level measurement is possible. It also has the calibration function to adjust the microphone level for each device.

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The WHO has proven direct links between noise and health risks; tinnitus, sleep disturbance, stress, cognitive impairment, heart diseases and annoyance in general. Please check your environmental noise for your wellness.

"Sound Level Analyzer" has received the highest rating as a sound level meter app in the research paper of acoustic academic journal "Applied Acoustics". (Paper: "Testing the accuracy of smartphones and sound level meter applications for measuring environmental noise", Enda Murphy, Eoin A. King ; Applied Acoustics 106(2016)16-22.)

Products Information

Version: 7.0
Release date: October 12, 2022. UTC
Size: 2.9 MB
Compatibility: Compatible with iPhone. Requires iOS 15.0 or later.
Category: Utilities, Life style
Status: Unsubscribe


Sound level measurement (dB)

- Leq (equivalent sound level), Min (minimum value), Max (maximum value), Avg (time average equivalent sound level)

- Frequency weighting correction characteristics: A (for noise level meter), C (for sound level measurement), Z (no correction)

- Time weighting characteristics: Fast = 0.125 sec, Slow = 1.0 sec

- Display Range: 0 - 130dB

Calibration function: level correction value settings, -20 to +20dB / 1dB unit
Measurement duration: 20sec


"Sound Level Analyzer" can be used with the following applications:

Live Sound
Environmental noise measurement
Setting and Tuning of Audio system
Installation of Audio equipments
Installation of Car audio equipments
Architectural acoustics
Device management

In addition, the followings are examples of the magnitude of the sound level in the measurement of environmental noise.

130dB: Engine sound of Airplane
110dB: Horn of Car
100dB: Noise of passing train
90dB: In loud factory
80dB: In the train, Vacuum cleaner
70dB: Noisy office, Noisy street
60dB: Quiet Car, Normal conversation
50dB: Quiet office
40dB: In the library, Quiet residential area
30dB: Outskirts of midnight, Whisper
20dB: Sounds of rubbing leaves

Note: The standard noise measurement range is 30 to 130dBA, and the measured value (Leq) is about 30dBA in a quiet room of the household. Due to the presence of background noise, noise levels are never measured at 0dBA even in very quiet environments.

Important initial settings (iOS permissions)

In order for this app to work properly, it is necessary to make the following initial settings related to the iOS system.

Microphone access permission setting

At the initial startup after installing the app, the iOS system asks for permission to access the built-in microphone. In this case, you need to enable access to "Microphone".

If you have not enabled this setting, this app can not work by privacy restrictions of the iOS system. Please enable the access permission on the iOS setting, "Settings > Privacy & Security > Microphone".


In addition, upon first launch, the iOS system will ask you to confirm App Tracking Transparency (ATT). Ads will be displayed with or without this permission, but if you choose to allow it, personalized ads will be delivered to you. This app is operated on the basis of advertising revenue, so we appreciate your cooperation.


Sound Level Measurement

This app makes the sound level measurement in general. In this case, by applying the appropriate Frequency Correction, Time Correction, and Level Correction, you can be the best sound level measurement.

Tap the play button to start the sound level measurement, and it then stop by tapping it again.


Sound level measurements are displayed measured values​ of Equivalent continuous sound level (Leq), minimum value (Min), maximum value (Max) and Time average equivalent sound level (Avg) in dB units. The Leq is also displayed as a color bar graph.

Leq: Equivalent sound level - Instantaneous value of sound level (noise level) (dB)
Avg: Time average equivalent sound level - Time moving average value (dB)
Min: Minimum sound level - Minimum value within the measurement time (dB)
Max: Maximum sound level - Maximum value within the measurement time (dB)

It also displays a short-term time variability graph at the same time. This graph shows the sound level fluctuations for the past 20 seconds. The graph shows the Leq level (white bar), the Avg level (green line), and the moving average level for 10 seconds (orange line).

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It can be measured as parameters, Time weighting correction, Frequency weighting correction, and Level calibration, to set as follows:

Time weighting correction

It specifies the time constant of calculating the sound level. Please set in accordance with the occurrence tendency and type of sound source.

FAST : 0.125 sec (Default)
SLOW : 1.0 sec

Frequency weighting correction

It is a weighting filter that limits the frequency band of the input signal. Please set according to the measurement applications.

A : A correction - Noise measurement by general audibility correction (Default)
C : C correction - Sound pressure level measurement for wideband sounds and music
Z : Non correction

Level Calibration

You can specify the reference level in the offset range. Tap the calibration value window in Info view, the input keyboard will appear. If you have the standard sound level meter, please use it to adjust the reference level.

Offset ranges : -20dB to +20dB in 1dB unit



Tap "Setting" button, it is displayed the product information and function description. The screen description can be scrolled up and down. Tap "Close" button, it will return to the main view.

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Release Note

Version 7.0 was released on October 12, 2022. UTC
Version 6.0.2 was released on January 9, 2022. UTC
Version 6.0.1 was released on December 24, 2021. UTC
Version 6.0 was released on November 7, 2021. UTC
Version 5.2 was released on March 26, 2021. UTC
Version 5.1 was released on August 23, 2020. UTC
Version 5.0 was released on May 21, 2020. UTC
Version 4.1 was released on March 28, 2019. UTC
Version 4.0 was released on November 14, 2018. UTC
Version 3.2 was released on May 18, 2018. UTC
Version 3.1 was released on March 15, 2018. UTC
Version 3.0 was released on February 27, 2018. UTC
Version 2.4 was released on January 23, 2018. UTC
Version 2.3 was released on May 17, 2017. UTC
Version 2.2 was released on June 2, 2016. UTC
Version 2.1 was released on March 4, 2016. UTC
Version 2.0 was released on December 21, 2015. UTC
Version 1.4 was released on December 4, 2015. UTC
Version 1.3 was released on March 24, 2015. UTC
Version 1.2 was released on September 3, 2014. UTC
Version 1.1.1 was released on July 13, 2014. UTC
Version 1.1 was released on June 23, 2014. UTC
Version 1.0 was released on June 10, 2014. UTC


This app is adjusted the reference value for iPhone. However, the built-in microphone of your iPhone is likely to have a non-uniform gain. The more exact measurement should be calibrated using the absolute level calibration devices.
The standard noise measurement range is 30-130dBA, and the measured value (Leq) is about 30dBA in a quiet room of the household. Due to the presence of background noise, noise levels are never measured at 0dBA even in very quiet environments.

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