Ultrasonic Analyzer vs Audio / Spectrum Analyzer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Ultrasonic Analyzer
This app provides real-time audio analysis with visual representations of sound frequencies. It allows users to listen to and analyze ultrasounds, with options for transposed playback and slowed-down analysis of inaudible sounds. It supports various sampling rates and offers detailed charting and measurement tools.
- Real-time spectrum analysis
- Spectrogram and oscilloscope views
- Octave RTA analyzer
- Transposed ultrasound listening
- Slowed-down playback
- High sampling rates up to 384kHz
- Zoom and pan capabilities
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Ultrasonic Analyzer is a real-time spectrum, spectrogram, oscilloscope, and octave RTA analyzer for your iPhone or iPad. It provides a visual representation of ultrasounds using a sampling rate of up to 384kHz**. You can listen to transposed ultrasounds* and analyze them in real time. For sounds that are normally inaudible, a slowed-down playback option is also available. Ultrasonic Analyzer can be used to analyze the calls of various animals (e.g., bats, dolphins), measure the frequency response of high-end audio equipment, or evaluate ultrasonic sensors. Additionally, it allows you to analyze short imported audio files within a spectrogram context. Features - Sampling rates: 44.1kHz, 48kHz, 96kHz, 192kHz, 200kHz, 250kHz, 384kHz** - Real-time transposed ultrasound listening during recording* - Spectrogram analyzer: Color and black & white modes - Spectrum analyzer - Oscilloscope (full FFT window size) - Octave RTA analyzer: Bands – full, 1/3, 1/6, 1/12 (RMS values) - Max/min Octave RTA values - dBFS Meter - Fast real-time response - Adjustable spectrogram frequency resolution - Configurable time interval between FFT computations, with values as low as 1ms or even lower - Fast Fourier Transform (FFT) - FFT window sizes: 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536 - Recording trigger: Automatically triggers based on specified frequency bands - Zoom and pan capabilities for all charts - Measurement tools available in all charts - Playback analysis - Transposition during playback - Slow-down playback: Transpose octaves down for easier analysis - Picture-in-Picture (PIP) mode: Allows simultaneous spectrogram analysis with a secondary chart (Octave RTA, Spectrum, or Oscilloscope) - Audio input support: Built-in microphone, external microphone (via USB camera adapter or iPhone/iPad dock connector – Core Audio compliant devices) - Sharing options: Share charts and audio recordings via email, social networks, or clipboard - Exporting capabilities: Save audio recordings (WAV) and image charts (PNG) to iOS Document Browser - Audio file import: Load short audio files from other apps or the iOS Document Browser - Supported audio formats: WAV, CAF, AAC, MP3 - Automatic sample rate conversion for imported files - Frequency scale options: Linear and logarithmic - Amplitude scale options: Linear and logarithmic (dBFS) - dBFS Meter weighting: dBZ (linear) - Adjustable spectrogram length (dependent on resolution settings) Tested with (via USB adapter): - Dodotronic Ultramic200K, Ultramic250K, Ultramic384K - Pettersson M500-384 - Avisoft UltraSoundGate 116Un Make sure you are using the latest iOS update. *Requires an external microphone with ultrasonic capabilities connected via a USB adapter. **Real-time analysis at a 96kHz sample rate or higher is only possible with an external USB microphone. Alternatively, you can import files recorded on an external device for non-real-time analysis.
Audio / Spectrum Analyzer
This application analyzes audio input from your microphone, displaying both the waveform and amplitude spectrum in real-time. It offers extensive customization for display, calculation, and signal generation.
- Simultaneous waveform and spectrum display
- Configurable display layouts
- Selectable FFT size and averaging
- Frequency weighting options (Flat, dBA, dBC)
- Octave band analysis
- Audio signal and noise generation
- Peak hold and pitch meter
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This RTA app supports simultaneous display of "Audio Waveform", as well as the FFT-based "Amplitude Spectrum" (frequency magnitude) and "Spectrogram" (frequency distribution over time), for audio signals input from a microphone. (FFT: Fast Fourier Transform, RTA: Real Time Analyzer) [Features] - Supports simultaneous display of Waveform / Spectrum / Spectrogram - Supports orientation both portrait and landscape - FFT size - Window function - Spectrum average - Spectrum Tilt - Frequency weighting (Flat, dBA, dBC) - The type of expressing the frequency of Spectrum / Spectrogram (Linear, Log) - Displays the peak level and its frequency of the spectrum - Peak Hold (displays the results of holding past peak values of the spectrum) - Octave Analysis (displays the spectrum divided into octave bands) - Generates the audio signal (Sine, Triangle, Squire, Saw) - Generates the noise signal (white noise, pink noise) - Pitch meter display The Pro version offers Ad-Free Viewing and High-Resolution Analysis (FFT size: 16384, 32768, Spectrum Average: 4, 8). [Setting items] 1. Screen structure : Select the display screen configuration. View Num : 1, 2 View Type : - 1 screen : Wave (Waveform) / 1D (Spectrum) / 2D (Spectrogram) - 2 screens : W+1D / W+2D / 1D+2D Layout : Vertical / Horizon 2. Frequency Axis Scale Type : Selectable the type of expressing the X direction (frequency) of Spectrum / Spectrogram. - Linear: Distributed at equal intervals - Log: The intervals increase logarithmically 3-1. FFT size : 1024, 2048, 4096, 8192, 16384, 32768 (* 16384, 32768 is available in the Pro version.) 3-2. Window function : Hanning, Hamming, Blackman, No window 4. Spectrum Average Number of spectrum average for a display of spectrum. 1, 2, 4, 8 (init value: 1) (* 4 and 8 are available in the Pro version.) Higher value will make the spectrum less noisy and more smooth, at the cost of lower time resolution. 5. Spectrum Tilt : Compensates the visual slope of the spectrum around a 1 kHz pivot. -6.0 to +6.0 dB/oct in 0.5 dB/oct steps (0 means no tilt). 6. Frequency Weighting : Selectable frequency weighting. - Flat: No frequency weighting is applied. - dB(A): Frequency response that takes into account human hearing. - dB(C): Relatively flat response. 7. Peak Hold : Displays the results of holding the past maximum values (peak values) of the spectrum. 8. Octave Analysis : Displays the results of classifying the spectrum into octave bands. Division method: - FFT: Spectral display - 1/24, 1/12, 1/6, 1/3, 1 octave: Display divided into octave bands Calc method: - Max: Displays the maximum spectrum value in each band - Average: Displays the average spectrum value in each band 9. Generates the audio signal : Set the audio signal to be generated. - There are 4 types of waveform. (Sine, Triangle, Squire, Saw) - It can set the value of the frequency in 20Hz - 20000Hz. 10. Generates the noise signal : Set the noise signal to be generated. - There are 2 types of noise. (White noise, pink noise) [Other] - Background color: Black, White - WaveForm: Line Color (Green, Yellow, Invert), Line Width (1.0 ~ 6.0 px) - Spectrum: Bar color (Green, Yellow, Color patterns) - Spectrogram: Colormap, Display range (-150 ~ -60 dB), Display time (4 ~ 60 sec), Apply Spectrum Tilt - Bluetooth connection policy selection (disabled, HFP, A2DP). - Scaling of Waveform / Spectrum display in the Y direction (magnification: 0.5 - 2.0). - Scaling of Spectrum / Spectrogram display in the X direction (magnification: 1.0 - 16.0).
Screenshots
Verdict
The clearest difference is price: Audio / Spectrum Analyzer at Free against Ultrasonic Analyzer's $19.99. Audio / Spectrum Analyzer also leads on rating (4.6 vs 3.9) and update cadence (every 2 weeks vs every 4 months). Ultrasonic Analyzer's advantage is in-app purchases (none vs 1) and ads (none vs shown). On device support 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
Audio / Spectrum Analyzer is free to download; Ultrasonic Analyzer costs $19.99 up front. Audio / Spectrum Analyzer sells 1 one-off in-app purchase. Ultrasonic Analyzer asks for nothing beyond the download.
Audio / Spectrum Analyzer holds the better App Store score, 4.6 against 3.9. That said, the two scores are not equally well evidenced: Audio / Spectrum Analyzer has 1K ratings behind it against 35, so its average is the more settled of the two. Written reviews point the same way: 57% of Ultrasonic Analyzer's written reviews are positive against 79% of Audio / Spectrum Analyzer's.
Ultrasonic Analyzer ships an update every 4 months, Audio / Spectrum Analyzer every 2 weeks. The most recent releases landed on September 23, 2026 and September 25, 2026 respectively.
| Parameter | Ultrasonic Analyzer | Audio / Spectrum Analyzer |
|---|---|---|
| Price | $19.99 | Free — better |
| Rating | 3.9 (35 ratings) | 4.6 (1K ratings) — better |
| Positive reviews | 57.1% of reviews | 78.6% of reviews — better |
| Number of ratings | 35 | 1K — better |
| Update frequency | Every 4 months | Every 2 weeks — better |
| Ads | No — better | Yes |
| In-app purchases | No — better | Yes |
| Monetization | Paid | Free with in-app purchases — better |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 12.4 — better | 17.0 |
| Further details — not scored | ||
| Size | 2 MB | 5 MB |
| Age rating | 4+ | 4+ |
| Developer | DEXUS Pawel Krzywdzinski | Loop-Sessions.LLC. |
Customer experience
Ultrasonic Analyzer
Audio / Spectrum Analyzer
Bugs and requests
Ultrasonic Analyzer
Not enough reviews yet to summarise bugs or requests.
Audio / Spectrum Analyzer
Reported bugs
3 issues- Stuck on latest measurement
- White noise instead of expected functionality
- Disconnects AirPods
Requested features
4 requests- Sampling rate adjustment
- Wave shape tracking
- Audio file analysis
- Octave analysis
In-app purchases
Ultrasonic Analyzer
No in-app purchases
Audio / Spectrum Analyzer
- Pro (Remove ads, High-Res analysis)$11.49
Questions
Is Ultrasonic Analyzer free?
Is Audio / Spectrum Analyzer free?
Which has better reviews, Ultrasonic Analyzer or Audio / Spectrum Analyzer?
Do Ultrasonic Analyzer or Audio / Spectrum Analyzer have ads?
Which is updated more often, Ultrasonic Analyzer or Audio / Spectrum Analyzer?
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