# Sound Spectrum Analysis — Audio Frequency Analyzer (RTA)

> Real-time audio frequency and sound spectrum analyzer with noise level measurement. (iPhone/iPad app by Dmitriy Kharutskiy.)

- Source: https://appshunter.io/ios/app/sound-spectrum-analysis/id1434975523 (this page in markdown: same URL + `.md`)
- Developer: [Dmitriy Kharutskiy](https://appshunter.io/developer/817385891)
- Category: Utilities, Music
- Price: Free with in-app purchases
- Rating: 3.60/5 from 41 App Store ratings · 34 written reviews indexed
- Age rating: 4+
- Requires: iOS 11.0 · 5 MB
- Languages: German (Germany), Russian, American English, Japanese
- Released: 2018-09-05
- Data updated: 2026-08-30
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/sound-spectrum-analysis/id1434975523/reviews.md

## What is Sound Spectrum Analysis?

The application is designed for analysis of a sound spectrum in real time (with a microphone). Besides, the application can be used as a measuring instrument of noise level (not for exact measurements).

• Sound wave.
• Fast fourier transform (FFT). FFT size: 2048 (the accuracy of determining the frequency of ±12 Hz), 4096 (±6 Hz), 8192 (±3 Hz), 16384 (±2 Hz), 32768 (±1 Hz), 65536 (±0.5 Hz), 131072 (±0.2 Hz).
• Linear and logarithmic frequency scale.
• Linear frequency scale with maximum details (there is a choice for the displayed frequency range).
• Linear and logarithmic amplitude scale.
• Octave bands (1/1, 1/3, 1/6, 1/12).
• Window functions (Blackman, Hamming, Hann (Hanning), Blackman–Nuttall, Gaussian, Flat top).
• A- and C-Weightings.
• Peak hold.
• Exponential spectrum averaging.
• Peak frequency detection.
• Values of any point (for frequency scale and sound wave (at maximum detail)).
• Sound level meter (dB SPL). You can calibrate your microphone by launching a signal generator with a sinusoid frequency of 1000 Hz on another device and making the volume very low. When the sound is almost inaudible, it is necessary to find the amplitude for the frequency of 1000 Hz on the spectrum (FFT size: 16384). This value should be multiplied by 1.2 (to compensate for spectral leakage). It will be the reference value for your microphone. ESTIMATE THE TOTAL NOISE LEVEL BY USING THE SOUND WAVE MODE AT THE MAXIMUM VALUE.
• Sample rate: 48000 Hz.
• Taking a screenshot by lightly touching the screen.
• Export data to a WAV or text file ("Y=[y1 y2... yn]", "y1;y2;... yn", "x1;y1\nx2;y2;..."). Number of points is adjusted via "FFT size".
• Automatic stop in the sound wave mode (when increasing or decreasing signal strength).
• Automatic stop in the spectrum mode. Now you can stop data collection when the start of the fading signal reaches the end of the FFT buffer. The beginning of the signal is not calculated accurately (just like with an automatic stop in the sound wave mode).
• Test wave.
• Saving the measurement results in the application. Files with saved data (SavedData_[date]_[time].txt) can be copied to a desktop/laptop computer or transferred to another iPhone using iTunes. There are buttons for quick loading and comparing saved files.
• Dark theme.
• List of frequency peaks. If several peaks have a common base, then they are considered as one peak. The minimum height of the peak for octave bands is 2 dB.
• Interpolation of frequencies in the list of peaks. To interpolate the frequency of the peak, select the Gaussian window (the accuracy of determining the frequency can increase by 10-100 times). The calculation is not done for the extreme bins or if the adjacent bin is zero.
• Calculation of the amplitude (in the list of peaks) using neighboring bins (to compensate for spectral leakage and use of the window). The number of bins used for calculation is written in brackets.
• Collecting recent data (last minute). You can move over all collected data. The amplitude of the waveform can be changed in the sound wave mode.
• Calibration file. The app recognizes only files for the UMIK-1 microphone, but you can specify which microphones you need support for.

## Key features

- Real-time sound spectrum analysis
- Fast Fourier Transform (FFT) with adjustable size
- Linear and logarithmic frequency/amplitude scales
- Octave band analysis (1/1, 1/3, 1/6, 1/12)
- Multiple window functions
- A- and C-Weightings
- Sound level meter (dB SPL)

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Full version | $2.99 | one-time |


## Recent user reviews (10 of 34)

All indexed reviews: https://appshunter.io/ios/app/sound-spectrum-analysis/id1434975523/reviews.md

### 5/5 — Best in class.

*2026-02-23, version 2.3.8*

This app has been my go to for spectrum analysis, accuracy is unmatched and the extra features are best bang for buck out there. I’ve tried the other offerings and they’re so gimmicky and focused more on looking good for waaaay too much money.

### 2/5 — Not useful for me

*2026-01-15*

The first problem I see is the frequency range is limited to 500hz on the low end. While trying to find a setting that would expand this, it reduced the range again even narrower. If there is a way to set the high and low frequency range, I cannot find it. Moving on…

**Developer response:** You can shift the range of frequencies displayed by swiping right or left. You can make the range of displayed frequencies wider or narrower using two fingers.

### 2/5 — Unfortunately very buggy

*2025-09-30*

Good when works. After couple recordings app just stops working, restarting doesn’t work at all. Only solution is to reinstall app

**Developer response:** Thank you for reporting the issue. Please email me so I can reproduce the issue. If it works at first and then stops working, maybe you changed some app settings?

### 1/5 — Needs developer attention

*2025-06-12*

All sections are paid except for a few non-functional ones! I wish they would play ads, but all sections were open! It's really annoying right now.

**Developer response:** Not all functions are paid. And the blocked functions are available in the full version of the app for $3. It's almost free. Those who show ads collect information about users in order to better manipulate and force them to pay much more than $3.

### 5/5 — HAHAHAHA

*2025-03-23*

made someone kick out someone else

### 5/5 — An astonishingly good App

*2025-03-06, version 2.3.5*

[UPDATE] 
Please ignore my little niggle … After closing and re-opening the App, the presentation is clean !

Worth every penny of the £2.99 upgrade price !

Just one little niggle … After buying, the money-bag icon still appears in the pop-up window. Surely purchasers deserve a clean presentation [!]

### 5/5 — An astonishingly good App

*2025-01-17, version 2.3.5*

Worth every penny of the £2.99 upgrade price !

Just one little niggle …
After buying, the money-bag icon still appears in the pop-up window.
Surely purchasers deserve a clean presentation [!]

### 5/5 — Nice

*2024-07-21, version 2.3.5*

Even design is great, thank you

### 5/5 — Great

*2024-06-09*

Glad I found this one. I had tried a few other apps but they didn’t give very good results. The paid version is definitely worth it.

### 4/5 — Need adjustable sample rate

*2024-03-01, version 2.3.5*

Would give 5 stars if the app could switch for higher sample rates

## Frequently asked questions about Sound Spectrum Analysis

### What does the Sound Spectrum Analysis app do?

This application analyzes the sound spectrum in real-time using your device's microphone. It can display sound waves, perform Fast Fourier Transforms (FFT) with various sizes for accuracy, and measure noise levels. It also offers detailed frequency and amplitude scales, octave band analysis, and various window functions.

### What are the key features of this app?

Key features include real-time sound wave and spectrum analysis, adjustable FFT sizes for frequency accuracy, linear and logarithmic scales for frequency and amplitude, octave band analysis, multiple window functions, A- and C-weightings, peak hold, exponential spectrum averaging, and a sound level meter (dB SPL).

### How can I calibrate the sound level meter?

You can calibrate the sound level meter by using a signal generator on another device to produce a low-volume 1000 Hz sinusoid. Find the amplitude for 1000 Hz on the spectrum (with FFT size 16384) and multiply it by 1.2 to compensate for spectral leakage. This value serves as the reference for your microphone.

### Can I save or export my measurements?

Yes, you can save measurement results within the application and export data to WAV or text files. Saved data files can be transferred to a computer via iTunes. The app also allows for quick loading and comparison of saved files.

### Is this app free to use?

The application is free to download and use, but it offers in-app purchases. These purchases likely unlock additional features or enhance the existing functionality beyond the basic free offering.

## Version history (last 5 releases)

### 2.3.8 — 2026-02-16

• Bug fixes.

### 2.3.7 — 2025-11-12

• Bug fixes.

### 2.3.6 — 2025-06-06

• A more detailed zoom level for the vibration wave (time scale).
• Minor changes in app design.
• Bug fixes.

### 2.3.5 — 2023-09-11

• Bug fixes.

### 2.3.4 — 2023-01-28

• Changing the start frequency of the logarithmic scale when zooming (moving along the logarithmic scale when zooming).
• Added black color theme.
• Adaptation for iPhone 14 Pro.
• Bug fixes.

## Apps similar to Sound Spectrum Analysis

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Noise Guru: Decibel Meter](https://appshunter.io/ios/app/noise-guru-decibel-meter/id6444836813) | 4.6 (299) | Free | Utilities |
| [Decibel X:dB Sound Level Meter](https://appshunter.io/ios/app/decibel-xdb-sound-level-meter/id448155923) | 4.6 (161,260) | Free | Utilities |
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| [Decibel Meter - Sound Analyzer](https://appshunter.io/ios/app/decibel-meter-sound-analyzer/id1579747105) | 3.5 (54) | Free | Utilities |
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All apps by Dmitriy Kharutskiy: https://appshunter.io/developer/817385891

## Related topics

[analysis sound](https://appshunter.io/ios/topics/analysis-sound) · [sound spectrum analyzer](https://appshunter.io/ios/topics/sound-spectrum-analyzer) · [sound measure frequency](https://appshunter.io/ios/topics/sound-measure-frequency) · [infrasound recorder](https://appshunter.io/ios/topics/infrasound-recorder) · [fft plot](https://appshunter.io/ios/topics/fft-plot) · [frequency meter](https://appshunter.io/ios/topics/frequency-meter) · [soun analyze](https://appshunter.io/ios/topics/soun-analyze) · [sound frequency meter](https://appshunter.io/ios/topics/sound-frequency-meter) · [sound oscilloscope](https://appshunter.io/ios/topics/sound-oscilloscope)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-30.*