DR14 T.meter is a commandline tool for computing the Dynamic Range of your music according to the procedure used in the offline meter released by the Pleasurize Music Foundation. It is very useful to measure how loud your music is and to understand that a good quality album always has a good dynamic. It's also useful for understanding the effects of the so-called loudness war.
Pimp is a highly interactive and programmable music player. It can be controlled with an mpd client or via a Python interpreter. Files can be played directly, and file paths are recorded in a database. Files are identified by a "fingerprint" which allows the user to identify an audio file despite file moving and tag modification. Pimp aims to be a player framework with a really small core. All features are implemented in extensions. For example, a lot of player events such as play, seek, and pause are logged in the database.
Flac-utils is a toolkit for managing FLAC files. Its primary usage is syncing metadata between sets of FLAC files. Flac-utils also provides a Python module called flac_compare that can be used separately. The utilitiy consist of three tools: flac-sync, which syncs a file tree of FLAC comments for files with the same audio-part; flac-diff, which compares two FLAC files' metadata information and shows the differences; and flac-add-picture, which adds album cover art to the files using Amazon.