Comparison of Media Players - Gnu/Linux

Media players are applications that handle the playing of audio and/or video. (In this comparison the listening of music will be the only factor, not how well/if these applications can play video.)
There is wide debate over which media player is superior, and this will list some of the pros and cons of each media player. Of course a lot of information is left out and of course there are a lot more than are listed, but this article will point a media player-hopper in the correct direction.

1. Clementine

 First off, I will state that Clementine is the application that I have used as of late for playing music. Playing music is what its specialty is. However, using Clementine to play a sound file would be overkill. It does a great job of saving your playlists for later listening and includes utilities for mass file renaming and organization.

Clementine can stream music from the internet and sync with devices. Common media player characteristics are included, such as shuffling and looping.

One of the selling points of Clementine is the ability to destroy the main window and have it reduce to the notification icon. From there you can control the volume, pause, play, move to next track, move to previous track, mute, love, ban, quit, or show the main window again. Clementine also integrates into the Ubuntu sound menu.

2. Amarok

  Amarok, the music player commonly paired with KDE due to the use of Qt, is the media player I had used before switching to Clementine. A very unique feature to Amarok that I had never seen before was the automatic fetching of information from wikipedia about the song and the fetching of lyrics. Of course, once the information was fetched it was cached and it does not rely on fetching to function properly. Amarok also integrates with your portable devices and will ask you before it begins to unlock them if they are locked, which can be troublesome if it misidentifies something to be a device.

Amarok is also capable of working without the existence of the main window. It will fall back to a notification icon with previous, pause, play, and next options as well as the option to show the main window.

3. VLC Media Player

VLC is a popular music player that is very good at what it does. It specializes in streaming but can also be used as a general purpose music player. If I have files that I do not want in my common playlist I use VLC since it does not save playlist information through usages. VLC does not excel with audio playback, but is rather used a video streaming/viewing application.

VLC, like Amarok and Clementine, has a notification icon but it cannot live without the main window. VLC has a very good equalizer

4. mplayer

 Mplayer has arguably the largest learning curve out of any of the media players. It does not come with a graphical frontend, so it must be run from the command line. It cannot remember playlists, you must make a playlist and start the application with the playlist as one of the arguments.

Mplayer has frontends available for it, like SMPlayer. Mplayer by itself does not work with the mouse, so you must memorize the keyboard commands to use it. Some find mplayer to be the best way to listen to audio since you can run it without a window or notification icon at all if you so please.

Interestingly enough, mplayer can play videos very well and is my video player of choice.

5. Rhythmbox

Rhythmbox is the default music player in Ubuntu 12.04. Banshee's absence has given Rhythmbox the opportunity to expand. Rhythmbox is now the official applications for the Ubuntu music store. Like Amarok and Clementine, Rhythmbox syncs to devices with arguably the most accuracy of the bunch. Rhythmbox does not have a notification icon and cannot live without keeping the main window open, so controlling the window may seem a bit bulky at first who are used to being able to kill the main window or control the flow of music through a notification icon.

6. DeadBeef

No, this media player is not built of mutilated cow. What it IS built with is C and GTK (I assume it is C, anyway.) The GTK dependency makes it lighter than a media player like Clementine that has Qt bindings. If you use a Gnome, XFCE, LXDE, *box, or Unity desktop environment; the download will only be about 5 MiB.

The Media player does not offer much in the way of customization or organization like Clementine, but it does get the job done like a media player should. It can import / export playlists, list statistics about the current playlist, and most importantly live without the main window and run as a daemon from the system tray. If you want to use Clementine without the elevated RAM usage and superfluous features, DeadBeef is the media player for you.
Honorable mentions
I did not include the following popular media players:

Banshee: Rhythmbox does nearly the same thing as Banshee.

XBMC: "VIM is a text editor; Emacs is an Operating System" is my favorite quote regarding text editors. XBMC is the Emacs of text editors. It is its very own ecosystem and would not be practical to use for multitasking. This is definitely the choice for a user wanting a heavily media-centric computing experience.

Conclusion (opinion)
I cannot call the conclusion fact since all of these media players do exactly what they are supposed to: play media. I just feel that Clementine has the best functionality. It can run in the background or have the main window; it doesn't matter to Clementine. It also does everything that Amarok can do like sync devices, fetch data, and live without a main window, so the presence of those features somewhat invalidates Amarok.

Bear in mind this opinion is only based in audio, and for video mplayer is my choice. I have no justification for this and VLC does just a good as job as mplayer.