A tag editor (or tagger) is an application which allows users to edit metadata of multimedia files. Metadata is the data about the audio data. It lets information about the audio file such as the title, artist, conductor, album, track length, lyrics, embedded images, and other information be stored in the audio file itself.
ZiK is an audio player based on gstreamer. It uses the path of your audio files instead of a music library. Audio files are shown on the left panel as they would be in a browser. The right panel is dedicated to the playlist. Both panels can be shown or hidden. ZiK uses your GTK theme.
Sourceforge: "Back in 2003, Minnesota developer Brian Langenberger began creating a set of labor-saving audio tools to convert FLAC files to MP3 files, MP3 files to WAV files, and other simple operations that were tiresome to do by hand."