Audio File Analyzer

Loop-Sessions.LLC.

Contains adsIn-app purchases

About this app

This app displays the "Audio Waveform" together with the FFT-based "Amplitude Spectrum" (frequency magnitude) or the "Spectrogram" (changes in frequency components over time) for audio files on your device.
(FFT: Fast Fourier Transform)
You can check the frequency components around the current playback position while playing the file.
It also supports transcribing audio from selected audio files.

[Features]
- Simultaneous display of audio waveform and a spectrum / spectrogram linked to the playback position.
- Supports both portrait and landscape orientation.
- Channel display switching (Mix / L / R).
- Displays the peak level of the spectrum / spectrogram and its frequency.
- Supports zooming in the frequency direction of the spectrum.
- Pitch meter display.
- Supports transcription.

The Pro version offers Ad-Free Viewing and High-Resolution Analysis (FFT size: 16384).

[Spectrum / Spectrogram Display Settings]
- Frequency Axis: Linear, Log
- FFT Size: 1024, 2048, 4096, 8192, 16384 (* '16384' is available in the Pro version.)
- Window Function: Hann, Hamm, Blkman, None
- (Spectrum) Octave Analysis: FFT, 1/24, 1/12, 1/6, 1/3, 1, Calc Method: Max, Ave
- (Spectrogram) Display Duration: 5–30 seconds, Display Range: -60 to -150 dB

[Transcription screen]
Transcribes speech in the selected audio file.
The results are divided into recognized speech segments and displayed in cells with their start times.
Tap a cell to move to that position.
Swipe left on a cell to copy its text.

Transcription feature utilizes the open-source Whisper speech recognition model.
Transcription is performed locally on your device; no data is sent externally.

What’s new

Added spectrogram display (can be toggled with the spectrum view).
You can configure the display orientation, time range, display range, and colormap.