Original Post — Direct link

The first track of all the music boxes is audible to the people around you and the music boxes give you a passive buff which plays music so you do not need to carry them around like the SAB Music Boxes. They are usable in combat and work in Open World, Dungeons, Fractals, Raids and WvW. They are not usable in PVP.

Dulfy has maps and videos out for all of the regular boxes which can drop these. They can also drop from big chests of various kinds but there are no comprehensive maps out there of those.

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over 6 years ago - /u/ArenaKeenan - Direct link

So glad everyone is enjoying these! Now if only they would drop for me... :)