I don’t particularly like the drum beat that plays when one logs into Ubuntu. It actually irritates me, since I often use my computer(s) at night, and I always cringe to think that someone living with me will wake up to that.
Anyhow, in Lucid the options to turn the startup sounds off wasn’t apparent to me. After searching a Launchpad bug, I found the options that do what I want.
To turn off the small sound when the computer boots and loads the login screen, go to
System > Administration > Login Screen. You will likely need to unlock those settings before editing. Simply uncheck
Play login sound.
The next part was harder to find, because I expect sounds to run as part of a hidden process that is toggled by a setting. Turns out the sound that plays when you log in is actually a lot simpler than that, it is just a start up application. To turn it off, go to
System > Preferences > Startup Applications. There will be an application listed called
GNOME Login Sound. Uncheck it.
Boosh, now you have a quieter machine on bootup/login. ^_^