Decibel is a GTK+ audio player designed for GNU/Linux. It aims at being very straightforward to use by means of a very clean and user-friendly interface. It aims also at being a real audio player and, as such, it does not include features that are not meant to be part of an audio player.
Deejayd is a multi purpose media player that can be completely controlled through the network using XML messages. It suppports playlists, searching, and many media tags. It can playback many music and video formats using either its xine backend (recommended) or its GStreamer backend.
DerMixD is an audio mixing and network-listening daemon that is similar to mixplayd but quite different in its implementation. It supports the playing of music files on a run-time configurable number of input channels, mixing them together and producing output on a run-time configurable number of output channels. It is controlled over a TCP socket and supports scripting, gapless playing of tracks, including filtering of null samples from padding, use of mpg123's equalizer, flexible input/output connection, changing playback speed, and more.
DigitalDJ is an SQL-based MP3-player frontend designed for people who want to create an MP3 version of their CD collection. It is designed to work with the Grip ripping/encoding application (but can be used separately). When Grip encodes MP3 files, it will place all of the song information into an SQL database. DigitalDJ can then use this information to create playlists based on a number of criteria.
ELMP:TNG Server is the server component of the Embedded Linux MP3 Player, a digital audio jukebox with some unique features. It is designed to run on customized PC hardware as part of a HiFi system or car stereo, but could also be used as a backend for a desktop MP3 player. Features include multiple playlists, a VFS layer, and plugins for decoder/output/vfs functions.
EQU is a realtime graphical equalizer that will equalize the audio of almost everything you play through XMMS (OGG, MP3, WAV, etc.). You can choose four different band configurations (10, 15, 25 and 31), all of them with ISO central frequencies, independent gain settings for left and right channels, and more than +-14dB of gain per band. It features a skinnable GUI and shadowed mode.