You’re sitting with your friends in a coveted booth at your favorite dive bar. The band starts into their third hour while intermittently pool table sounds pierce through the excited chatter of a few hundred other patrons, their glasses and bottles clinking. Your in-ear monitor is presenting you with all of these sounds, but their volume has been carefully adjusted, as if by a sound engineer, so that you can focus on the resonate tones of your friend’s voices around the table. You can cle...