[ranger danger]

Your initial concerns were valid! A new driver, in my opinion, has no business with a stereo so loud that they can not hear necessary sounds (sirens, horns, screams from pedestrians etc). This is a safety issue! Its also rude and inappropriate in many situations. I would have asked the shop owner to turn down the gain on the amplifier so that it would not go so loud. Then I would have instructed my son that he was not to operate the system at loud volumes until I was comfortable with them. All of this being said, You are learning some valuable lessons. Good luck!