Earbuds for music with an ipod. Can still hear engine and external noise. Great sound and way better than anything you'll get with a more traditional stereo system, at least in my opinion.
https://www.etymotic.com/
These earplugs when just driving, even with a helmet on the track. Can still hear everything that is necessary.
https://www.surefire.com/ep3-sonic-defenders.html
I seldom drive w/o some form of ear protection. Never had a problem with LE in 65k Cobra miles. I would not sacrifice my hearing, or what's left of it, to avoid a ticket.
I've looked at communication systems, not for road use but for track sessions but haven't spent the money. There are many varieties and sources.
Jim