A Look at the Speaker-Amplifying Kin Battery Cover
"Back in the day i was really into car audio and one of the things i was fascinated with was the designing and building of speaker boxes. The basic reason a speaker needs a box is to combat the cancellation of the in and out of phase sound waves. When a speaker makes a sound the cone moves forward, but the cone must move back to its original position it also makes a sound firing in the opposite direction. These two sound waves are opposites or what is referred to as our of phase. So what the speaker box aims to do is to negate these backward cone movements with a sealed and angled charmers."
It's pretty slick how the Kin was designed to amplify the power of the on-board speakers...clever design is great to see in any product!