DESCRIPTIONThe beep command rings the keyboard bell. Percent is relative to the base volume of the keyboard bell and can range from -100 to 100 inclusive.
If percent is nonnegative then the bell volume is:
base - [(base * percent) / 100] + percent
If percent is negative then the bell volume is:
base + [(base * percent) / 100]
The default percent is 50.