Add Charging Sound to Your MacBook Using Terminal Command
When you plug in your iPhone, you hear a very pleasant ringing signal that everything is fine. If you want to achieve the same sound effect on your MacBook, OS X Daily shows you how.
There is already a visual indicator on your MacBook’s power cord to indicate that it is plugged in, but adding a little sound effect is easy. Just open Terminal (Applications> Utilities) and enter this, then press Return:
by default write com.apple.PowerChime ChimeOnAllHardware -bool true; open /System/Library/CoreServices/PowerChime.app &
That’s it, plug in the power adapter and you will hear the same beep as on iOS.
How To Play Power Charging Sound Effect In OS X When MacBook Is Connected To A Network (For example iOS) | OS X Daily