How to set up Apple computers to turn off the startup sound:

1. Run "Terminal";

2. Enter sudo nvram SystemAudioVolume=%80 in the terminal, And click Enter; 3. Enter the administrator password and press Enter to confirm.

4. Try shutting down and restarting. This will turn off the Mac startup sound.

Turn on the Mac startup sound:

If you want the startup sound to reappear, you can also do it through the Terminal application.

1. Run "Terminal";

2. Enter sudo nvram -d SystemAudioVolume;

Note: This method is applicable to all OS X system versions.

Apple's Apple II fueled the personal computer revolution in the 1970s, and the subsequent Macintosh relay continued to develop in the 1980s. The most well-known products are its Apple II, Macintosh computers, iPod digital music players, iTunes music store and iPhone smartphones. It is famous for its innovation among high-tech enterprises.