Snack provides commands to play, record, process, and visualize sound.
It supports various file formats such as WAV, AU, AIFF, and MP3.

With Snack, you can easily create sound applications with Tcl/Tk or
Python or extend existing programs with sound capabilities.

The documentation is located under /usr/share/doc/packages/snack There
is also a 'demos' subdirectory which contains examples for Tcl/Tk and
Python.