Chronograph is the app for syncing song lyrics by timestamps.
Whisper
Whisper allows you to listen to your microphone through your speakers.
Festival
Festival is a music player for local album collections.
G4music
A beautiful, fast, fluent, light weight music player..
Amberol
A small and simple sound and music player.
Picard
MusicBrainz Picard is a cross-platform (Linux, macOS, Windows) audio tagging application.
Carla
Carla is a fully-featured modular audio plugin host, with support for many audio drivers and plugin formats.
Surge
A sound designer’s dream. A friendly, open community.
Solfege
When you study music on high school, college, music conservatory, you usually have to do ear training. GNU Solfege tries to help out with this.
Youplay
Search, download and play music from YouTube.