The best Media Center alternative to Spotify is Ampache, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Spotify and three of them are Media Centers so hopefully you can find a suitable replacement. Other interesting Media Center alternatives to Spotify are Koel and Finamp.
Ampache is a web based audio streaming application and file manager allowing you to access your music from anywhere, using almost any internet enabled device.
A personal music streaming server that works.
If you want to use the mobile apps, you have to pay for it.
Finamp is a Jellyfin music player. Its main feature is the ability to download songs for offline listening.
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