"Manually" start a music or sound in a region

[TheGr00m]

Could it be (or is it already) possible to manually start a music or sound in a region?

Like, set a region, when one or several player(s) enters it, nothing is played, but when a command block with the command "/jukebox music/sound @a <direct_link> {region_name}" is activated, the player(s) hears it.

[oliverdunk]

Would shows (documented on our Spigot page) work here? They're basically a way to add people to a group when they enter a region, and then play audio for them all in sync at a time of your choosing.