Debian GNU/Linux - Turning the Beep On or Off

If you don't want the X display to beep (for instance, when you send a control-G or ``bell'' character to xterm), you can turn it off using:

[user@hostname]~$ xset b off

to turn the beep on, use:

[user@hostname]~$ xset b on

More info:
http://l4u-00.jinr.ru/usoft/WWW/HOWTO/Custom-X-Tips-5.html