When I ride alone I listen to music on my earphones, but only wear the right one, I can hear traffic pretty well this way. When I'm out with my SO on group rides we use a speaker to play music on a moderate level (it's only for us, anyway). Currently I use one that a coworker lends me strapped to my handlebar and connected via bluetooth to my phone (while I wait for the cheapie speaker I ordered from Aliexpress to arrive lol). Other riders haven't complained, if anything they show interest in what we're listening to. To each their own.