Yes this is possible, but they are more workarounds than a direct support system you might be looking for.
1. If you can use an Android device, you can use an app called SoundSeeder, which intigrates Google Music support to share/play a playlist or music on your device and have friends listen at the same time.
2. On iOS devices you can try two apps. 1) Madsonic or 2) AmpMe.
3. You can purchase "Bluetooth Splitters", but they may not work for how many people you have and the distance you may be from each other.
Honestly, your best bet is using a service like Google Music, where you pay $9 a month for access to ALL MUSIC(and I mean everything), and building a playlist you share with everyone who starts playing it at the same time(relatively).
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