Get Rid Of The Mac Startup Chime [OS X Tips]

Macs are distinctive among the computing fraternity in the melodious chime they make while booting. While PCs that do nothing more than beep might look on enviously, the fact is that the chime isn’t always welcome—boot your MacBook in a library, for example, and several annoyed faces will willingly hand out censure.

Here’s how to turn off the chime. These instructions are created for OS X Lion but should work with older versions of OS X.

Here’s another tip from the new book Mac Kung Fu, which contains over 300 tips, tricks, hints and hacks for OS X. It’s available from Amazon as well as other bookstores, and also as an eBook for all eReaders. 

Because there’s no official way of deactivating the boot chime (via a hardware settings switch, for example), the solution below is a hack that works by muting your computer’s volume when you shut down and then unmuting it when you log in again upon rebooting. Unfortunately, if you’re using OS X Lion this only works if you don’t have FileVault turned on, because that uses a different login procedure.

Follow these instructions exactly. Don’t use a different text editor such as TextEdit! TextEdit outputs plain text files that–perhaps because of a bug–cannot be interpreted as boot-time scripts, which is a vital part of this procedure.

1. Open Terminal (Finder->Applications->Utilities->Terminal) and type nano, to open the nano command-line text editor. Then copy and paste the following two lines within nano:
   #!/bin/bash
osascript -e 'set volume with output muted'
2. When you’ve finished typing, hit Control + O, then copy and paste the following for the filename:~/Documents/mute.sh. Hit Return to save the file. See the screenshot for an example of how it should look.
3. Don’t close the Terminal window, but alter the second line within nano to read as follows (that is, changewith to read without):
   #!/bin/bash
osascript -e 'set volume without output muted'
4. When you’ve finished typing, hit Control + X, hit Y, then copy and paste the following for the filename:~/Documents/unmute.sh. Hit Return to save the file. nano will quit.
5. In the Terminal window copy and paste the following series of commands, typing your login password when prompted (copy and paste each line individually, hitting Return after each; note that the last two lines are actually one line but are broken in two because of website formatting issues–just copy both lines at once, then paste):
   sudo chmod u+x ~/Documents/mute.sh
sudo chmod u+x ~/Documents/unmute.sh
sudo mv ~/Documents/mute.sh /Library/Scripts/
sudo mv ~/Documents/unmute.sh /Library/Scripts/
sudo defaults write com.apple.loginwindow LogoutHook /Library/Scripts/mute.sh
sudo defaults write com.apple.loginwindow LoginHook /Library/Scripts/unmute.sh

When you reboot, you should find the chime volume is now muted.

Paste the script, hit Ctrl + O, then type the filename, as highlighted

To restore the chime at a future date, open a Terminal window and copy and paste the following series of commands, hitting Return after each line, and again typing your login password when prompted:

sudo defaults delete com.apple.loginwindow LogoutHook
sudo defaults delete com.apple.loginwindow LoginHook