Decibel X vs Audio Frequency Analyzer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Decibel X
This tool transforms your device into a professional sound level meter, offering precise measurements of ambient noise. It features advanced calibration, frequency analysis, and data management for various applications, from personal curiosity to professional use.
- Pre-calibrated sound pressure level (SPL) measurements
- Frequency weighting filters (dBA, dBC, ITU-R 468)
- Apple Watch and Health App integration
- History data management with export options
- Dosimeter with NIOSH, OSHA standards
- FFT and BAR graphs for real-time frequency analysis
- InstaDecibel for sharing dB reports on photos
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"Decibel X" is one of very few noise meter apps on the market that has highly reliable, pre-calibrated measurements and supports dBA, dBC. It turns your iOS device into a professional sound level meter, precisely measures the sound pressure level (SPL) all around you. This extremely useful and beautiful tool will not only be a great tool for many uses but also bring you a lot of fun. Have you wondered how quiet is your room or how loud is a rock concert or sport event? "Decibel X" will help you answer all of those. WHAT MAKE IT GREAT AND STAND OUT FROM OTHER APPS: - Trusted accuracy: the app is tested and pre calibrated for all Apple devices. The precision is matching with real SPL devices - Apple Watch support: see noise level right from your wrist - Health App integration: export noise levels directly into Health app - Frequency weighting filters: ITU-R 468, A, B, C, Z - Powerful, smart history data management: + Recording data can be saved into a list of history records for future access and analysis + Each record can be exported as hi-res PNG graph or CSV text via sharing services + iCloud support which synchronize all history records across your Apple devices + Fullscreen mode to give overview the whole history of an record - Dosimeter with NIOSH, OSHA standards - Powerful calibration: Linear, Octave 1/1, 1/3, Load/save profile - FFT and BAR graphs to display real time FFT. Those are very useful for frequency analysis and musical tests. Real time predominant frequency is also displayed. - InstaDecibel to capture your dB report overlaid on photos and easily shared via popular social networks (Facebook, Instagram, Messages, etc.). - Support Live Activity, Dynamic Island - Support both Portrait and Landscape layouts - Beautiful, intuitive and carefully crafted UI design. Themes: LIGHT, DARK and CLASSIC OTHER GREAT FEATURES: - Standard time weightings (Response Time): SLOW (500 milliseconds), FAST (200 milliseconds) AND IMPULSE (50 milliseconds) - MIC Gain Offset from -50 dB to 50 dB - Standard measurement range from 30 dBA up to 130 dBA - HISTO graph for plotted history of the recorded values - WAVE graph with 2 display modes: Rolling & Buffer - SPECTROGRAPH - Real time scale level chart - Display Current, Average/Leq, and Max values with both nice and clear digital and analog layouts - Quick reference text to help you compare with real-life examples NOTES: - Please do not expect a quiet room reading will be 0 dBA. The range 30-130 dBA is the standard usable range and an average quiet room will be about 30 dBA. - Although all devices are pre-calibrated, custom calibration is suggested for serious purposes requiring higher precision and accuracy. You will need a real external device or calibrated sound meter as a reference, then adjust the trimming calibration until the reading matches with the reference. * Privacy Policy: http://www.skypaw.com/decibelx/privacy_policy.html * EULA: http://www.skypaw.com/decibelx/terms.html
Audio Frequency Analyzer
This real-time audio analyzer measures and evaluates sound environments with 1/3 octave band frequency response and FFT analysis. It supports calibration for high accuracy and is suitable for various audio testing and tuning applications.
- Real-time frequency spectrum response measurement (1/3 octave, 30 bands)
- FFT Analyzer
- Observation frequency range: 20 - 23000 Hz
- Calibration function for high accuracy
- Supports built-in and external microphones
- Snapshot and averaging functions
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"Audio Frequency Analyzer" is a powerful real-time audio analyzer (RTA) app for iPhone. With its simple operation, you can easily measure and evaluate your sound environment. This app measures the frequency response in 30 split band scale of 1/3 octave in real time. It can also display the FFT analysis results. It supports calibration for 1/3-octave bands. By adjusting the characteristics to match not only the built-in microphone but also your external microphone, it achieves high measurement accuracy. "Audio Frequency Analyzer" can be used for various applications, including sound room tuning, speaker settings, audio equipment testing, stage setup measurement, sound mixing environment evaluation and noise environment investigation. Features: - Frequency spectrum response measurement of 1/3 octave unit, 30 bands. (OCT) - FFT Analyzer (FFT) - Observation frequency range: 20 - 23000 Hz - Logarithmic amplitude display. - Touch-scroll function to adjust visible amplitude ranges. - Display the measured value of 1/3 oct bands at OCT mode. (dB@OCT) - Function to change the graph slope at FFT mode. (Slope): -3dB/oct (less than 1kHz), +3dB/oct (1kHz or higher) - Peak hold function. (Hold) - Average display function. (Avg): Time linear averaging. Fast-2.56sec, Slow-12.8 sec - Display response control. (Fast/Slow) - Reset of Measurement display position. (Scroll) - Snapshot of Measurement display. (Snap) - Calibration function in OCT mode. (Calibrate): 1/3 octave band offset and total offset setting. - Supports built-in microphone, headset microphone, and external digital audio connection. Note: The first time you access your microphone and photos after installing the app, the iOS system will ask you for permission to access them. If you have not enabled this setting, the app will not be able to access them due to iOS system privacy restrictions. Please enable the access permission in the iOS setting "Settings > Privacy & Security > Photos or Microphone". Please visit our iOS app support page for more information about this app.
Screenshots
Verdict
The clearest difference is price: Decibel X at Free against Audio Frequency Analyzer's $9.99. Decibel X also leads on rating (4.6 vs 3.7) and ratings volume (164K vs 3). Audio Frequency Analyzer's advantage is in-app purchases (none vs 5). On review sentiment and ads there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Decibel X is free to download; Audio Frequency Analyzer costs $9.99 up front. Decibel X sells 5 in-app purchases, starting at $1.99 per 7 days. Audio Frequency Analyzer asks for nothing beyond the download.
Decibel X holds the better App Store score, 4.6 against 3.7. That said, the two scores are not equally well evidenced: Decibel X has 164K ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 66% of Decibel X's written reviews are positive against 60% of Audio Frequency Analyzer's.
Decibel X ships an update every 3 months, Audio Frequency Analyzer every 8 months. The most recent releases landed on November 4, 2026 and November 1, 2026 respectively.
| Parameter | Decibel X | Audio Frequency Analyzer |
|---|---|---|
| Price | Free — better | $9.99 |
| Rating | 4.6 (164K ratings) — better | 3.7 (3 ratings) |
| Positive reviews | 66.3% of reviews — better | 60.0% of reviews |
| Number of ratings | 164K — better | 3 |
| Update frequency | Every 3 months — better | Every 8 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Freemium — better | Paid |
| Devices | iPhone, iPad, Apple Watch — better | iPhone |
| Requires iOS | 17.0 — better | 26.2 |
| Further details — not scored | ||
| Size | 90 MB | 0 MB |
| Age rating | 4+ | 4+ |
| Developer | SkyPaw Co., Limited | TOON,LLC |
Customer experience
Decibel X
Audio Frequency Analyzer
Bugs and requests
Decibel X
Reported bugs
3 issues- App crashes when deleting recordings
- Microphone issues on certain devices
- Saved files not accessible after updates
Requested features
5 requests- Add GPS coordinates to recordings
- Improve reporting and data export
- Provide more weighting options
- Extend frequency range
- Allow music playback while using the app
Audio Frequency Analyzer
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Decibel X
- Weekly Membership$1.997 Days
- Monthly Membership$5.991 Month
- Annual Membership3 Days trial$49.991 Year
- ITU-R 468, A, B, C Weightings$1.99
- Data Export$2.99
Audio Frequency Analyzer
No in-app purchases
Questions
Is Decibel X free?
Is Audio Frequency Analyzer free?
Which has better reviews, Decibel X or Audio Frequency Analyzer?
Do Decibel X or Audio Frequency Analyzer have ads?
Which is updated more often, Decibel X or Audio Frequency Analyzer?
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