Spectrogram

Galmiza

About this app

Spectrogram shows the sound picked up by your microphone in real time: the waveform at the top and, below it, a scrolling spectrogram of every frequency up to 22 kHz.

• FFT resolution from 32 to 65536 points
• 9 window functions to reduce spectral leakage: Rectangular, Triangular, Welch, Hanning, Hamming, Blackman, Nuttall, Blackman-Nuttall, Blackman-Harris
• Linear or logarithmic frequency scale
• 4 color palettes: Fire, Ice, Grey, Rainbow
• Pause and resume at any time; drag vertically on the waveform to zoom
• Follows your phone's light or dark theme

The sound is analysed on your device only: nothing is recorded, stored or sent.

Levels are relative to the loudest sound the microphone can capture. They are not absolute sound pressure levels, which would require calibrating each phone's microphone.

Free and ad-free. Source code: https://github.com/galmiza/spectrogram-android

Ratings and reviews

Not useful for linguists. The scale of the x axis is more than 10 seconds and you can't zoom in, meaning you won't get a useful look at any phenomena with timing on the order of milliseconds. Seems like it was designed for musicians, but it would be nice if it were usable for other things, too. The ability to record a short token and zoom in on the spectrogram in one- or even half-second increments would be ideal.

Works very well overall. Using with VLF antenna to capture sounds on the go. Would be useful if there was an option for real time audio playback for those of us using this app as a real tool for more than mic input. Would be nice to get some mains hum FFT filtering too. Sitting out here with my antenna the app is great but not very useful without being able to hear the audio as well. Please add these features and I will give 5 star!

Works but could use a lot of improvements as the spectrogram is so tiny, the top bar and utterly unnecessary oscilloscope take valuable screen space. Log mode stops showing frequency bar on the right.

What’s new

Version 2.0, rewritten for today's Android:
• New design that follows your light or dark theme
• Smoother spectrogram that scrolls at a constant speed
• Corrected Blackman, Nuttall, Blackman-Nuttall and Blackman-Harris windows
• The microphone stops as soon as the app leaves the screen
• Your settings are kept