If you don’t like the Windows 7 Startup Sound then you may disable it. Another reason for disabling it may be to mute your laptop in a class room or a meeting room where you want to maintain silence. Well, the startup sound is not long but if the laptops volume isn’t muted then it will heard by everyone.
Go to Start> Control panel> Sounds.
A new window will open like the one shown above. Click on Sounds and uncheck ‘Play Windows Startup Sound’.
Click OK and exit.