piCorePlayer is described as 'Software emulation of a Squeezebox network music player that runs exclusively on the Raspberry Pi' and is a Audio Player in the audio & music category. There are more than 50 alternatives to piCorePlayer for a variety of platforms, including Windows, Linux, Mac, Android and iPhone apps. The best piCorePlayer alternative is foobar2000. It's not free, so if you're looking for a free alternative, you could try foobar2000 or AIMP. Other great apps like piCorePlayer are MusicBee, Winamp, Audacious and Strawberry.
Juk is a music player and a music manager. JuK is, well, at its heart, a jukebox. As is typical with many jukebox applications, JuK allows you to edit the tags of your audio files, and manage your collection and playlists. JuK is part of the KDE Multimedia package.
Germany
EU
Kantaris is an all new media player based on code from Videolan client (http://alternativeto.net/software/vlc-media-player/) and Bass audio library. Kantaris has a graphical user interface similar to that of Windows Media Player.
SwedenEU
Music is the new GNOME music playing application. It aims to combine an elegant and immersive browsing experience with simple and straightforward controls.
United States
MPlayer for Windows (modified by william0wang) with many additional features:
United Kingdom
Boom is an easy to use audio player intended for casual computer users who do not wish to spend their time on figuring more sophisticated software out. All of its most important features are easily accessible out-of-the-box.
PolandEU
Voltra is a minimalist music player with cloud sync, offline playback, and lossless support.
VVave manages your music collection by retrieving semantic information from the web, create playlists, tag music tracks, support for remote streaming using Nextcloud, and allows you to watch YouTube content.
Mexico
Sonique is an audio player application released as freeware for Microsoft Windows, capable of handling MP3, Ogg Vorbis, Microsoft Windows Media, audio CDs, and more.
In essence a lightweight music player that also have folder browsing, equalizer, song cross-fading and video playback capability.
PolandEU
A music player that connects to your cloud/distributed storage, in the form of a static, serverless, web application.
A music player for FLAC, MP3, MP4, streams, … with playlist support and SONOS integration.
