Apple PowerBook (Duo 270C) - Manual (Page 148)

3. Click the beep sound that you want your computer to
use.
When you click a sound to select it, it’s played at the current
volume setting.
4. Drag the slider up or down to set the volume.
If you set the volume to zero, instead of hearing a beep, you’ll
see the menu bar flash.
5. Close the Sound control panel.
Installing a sound
Your computer comes with several beep sounds. You can get
additional sounds from various sources.
m To install a sound, you drag its icon to the System
Folder icon (not the System Folder window). The sound
is automatically installed in the System file, where it
belongs.
Once you add a sound to the System file, it is listed in the Sound
control panel.
132 Chapter 9: Sound, Color, and Video