Comparison

Sound Level & Spectrogram vs Zephyr Control

Price, ratings, monetisation and update history for both apps, side by side β€” with what reviewers say about each.

Head to head
About

Sound Level & Spectrogram

Measure sound levels in decibels and visualize sound frequencies with a real-time spectrogram. Understand your environment's noise and protect your health. Offers advanced settings for accurate acoustic analysis.

Highlights
  • Sound level measurement (dB)
  • Real-time spectrogram analysis
  • Frequency weighting correction (A, C, Z)
  • Time weighting characteristics (Fast, Slow)
  • Time course graph
  • Environmental noise measurement
Read full description

"Sound Level & Spectrogram" is a sound level meter app for iPhone to easily measure the sound level of noise and music in your living environment. Simply tap the start button to measure sound levels in decibels (dB) and view the real-time variation of the sound level. You can also use the spectrogram feature to visually check the frequency characteristics of the sound source. Furthermore, you can select between frequency weighting correction characteristics and time weighting characteristics, which are essential for standard sound level meters, enabling appropriate sound measurement. Exposure to noise can impact health, potentially causing tinnitus, sleep disorders, stress, cognitive decline and heart disease. These risks have also been highlighted by the World Health Organization (WHO). Understanding noise levels is the first step towards improving your quality of life. Use this app to protect your health and create a comfortable living environment. Features: - Sound level measurement (dB): Leq (equivalent sound level), Min (minimum value), Max (maximum value), Avg (time-averaged equivalent sound level) - Frequency weighting correction characteristics: A (general sound level measurement with auditory correction), C (sound level measurement with almost flatter correction than A correction, e.g. peak evaluation at high volume), Z (flat characteristics without auditory correction, physical sound level measurement) - Time weighting characteristics: Fast=0.125sec, Slow=1.0sec - Time course graph - Spectrogram: 1/3 octave band analysis - Measurement time: 20 sec Applications: - Environmental noise measurement - Architectural acoustics - Live sound check - Installation of audio equipment - Tuning of sound equipment - Device management Example of the noise level situation: - 130 dB: Engine sound of Airplane - 110 dB: Horn of Car - 100 dB: Noise of passing train - 90 dB: In loud factory - 80 dB: In the train, Vacuum cleaner - 70 dB: Noisy office, Noisy Street - 60 dB: Quiet Car, Normal conversation - 50 dB: Quiet office - 40 dB: In the library, Quiet residential area - 30 dB: Outskirts of midnight, Whisper - 20 dB: Sounds of rubbing leaves Note: - Spectrogram is a tool to analyze the frequency spectrum of sound, with time on the horizontal axis, frequency on the vertical axis, and the strength of the signal represented by colors, and is used for acoustic analysis, voiceprint identification, etc. - 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. Therefore, exact measurements are not guaranteed. - The standard noise measurement range is 30-130 dBA, and the measured value (Leq) is about 30 dBA 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. In a typical anechoic room, the noise level is around 5-15 dBA. - 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 the microphone. If you have not enabled this setting, this app cannot work by privacy restrictions of the iOS system. Please enable the access permission on the iOS setting, "Settings > Privacy & Security > Microphone". Please visit our iOS app support page for more information on this app.

About

Zephyr Control

Features
Read full description

Zephyr Control Revolutionize the way you manage your air handling unit. Zephyr Control is the innovative app designed to provide seamless, remote access to your Tecniplast Air Handling Unit (AHU). Whether your AHU is equipped with a touchscreen interface or not, this app mirrors the device interface directly on your mobile device, giving you full control and visibility anytime. Key Features: Remote access to your Tecniplast AHU interface Real-time monitoring and configuration Compatible with both touchscreen and non-touchscreen AHU models Secure connection for peace of mind Intuitive design for easy navigation and operation

Screenshots

Sound Level & Spectrogram4 screens
Zephyr Control2 screens

Verdict

The call

The clearest difference is ads: Zephyr Control at none against Sound Level & Spectrogram's shown. On price, update cadence, in-app purchases and device support there is nothing between them.

Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Sound Level & Spectrogram ships an update every 5 months, Zephyr Control every 6 months. The most recent releases landed on October 6, 2026 and October 1, 2026 respectively.

Scorecard1 real difference Β· 7 level
Sound Level & Spectrogram versus Zephyr Control: the parameters behind the verdict, then further details
ParameterSound Level & SpectrogramZephyr Control
PriceFreeFree
Positive reviews100.0% of reviewsβ€”
Update frequencyEvery 5 months β€” betterEvery 6 months
AdsYesNo β€” better
In-app purchasesNoNo
MonetizationAd-supportedβ€”
DevicesiPhoneiPhone, iPad β€” better
Requires iOS18.717.0 β€” better
Further details β€” not scored
Size4 MB40 MB
Age rating4+4+
DeveloperTOON,LLCTecniplast SpA

In-app purchases

None

Sound Level & Spectrogram

No in-app purchases

None

Zephyr Control

No in-app purchases

Questions

Is Sound Level & Spectrogram free?
Sound Level & Spectrogram is free to download, with no in-app purchases.
Is Zephyr Control free?
Zephyr Control is free to download, with no in-app purchases.
Do Sound Level & Spectrogram or Zephyr Control have ads?
Sound Level & Spectrogram shows ads; Zephyr Control does not.
Which is updated more often, Sound Level & Spectrogram or Zephyr Control?
Sound Level & Spectrogram ships an update every 5 months, and Zephyr Control every 6 months. Most recently, Sound Level & Spectrogram was updated on October 6, 2026 and Zephyr Control on October 1, 2026.

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