Spettro shows a scrolling spectrogram of music as it plays
Spettro has a logarithmic frequency axis, which allocates the same amount of space to each octave.
It can play most audio files (WAV, OGG, FLAC, MP3, M4A and even the soundtrack of videos) and shows a scrolling spectrogram of it with a vertical green one-pixel-wide line half way across the window to show the current playing position.
You can also:
spettro showing the start of Wish You Were Here, with all the axes turned on.
Had you ever noticed the rising and falling sine wave you can see at the top?
There is a screencast of it on YouTube
It is known to run on GNU/Linux and should be portable to Windows, Mac, Android, iOS and Tizen.
Or, for the latest development version,
git clone https://gitlab.com/martinwguy/spettroThere are packages for Debian and Ubuntu under martinwguy.net/spettro/release and spettro is included in the "unstable" repository of deb-multimedia.org.
sudo make install
Planned features and improvements are listed in TODO, known bugs in BUGS.