The speakers were used on the terminals more so than PCs and, from what I remember, all they really did was beep when you pressed a key to acknowledge said keypress. If they did any more than that, I would be both unaware and suprised.
The sad thing is that I am old enough to remember this.
The even more sad thing is that my company still has these terminals in use. Most of us use terminal emulators (3270s), though. Mainframes are still the masters of uptime. Unfortunately, I have been dealing with the reprocussions of our mainframe's job scheduler crashing last night. Ugh.