Your car is not a cone-of-silence. You can (and will) be heard.
Over-estimating the sound proofing of your car can be highly entertaining. For your passengers and the occasional pedestrian.

This is part of my 101 Ways to Live series (follow the link to read the original post). The illusion of being in your very own private bubble is highly liberating. You can really set free and let loose on your favourite tunes. It is one of the last “shame free” zones, provided you’re not driving like a crazy person.
So crank up the volume.