Another popular cartoon series on TEC was the monolith series. Where we see constant monoliths in space, and they crumble revealing the sound of the day.
Let me see if I can list them all.
AI - aliens nudge each other on the shoulder and whisper "AI!" into the next one's ears. The last one bumps the monolith by mistake. (Didn't something similar happen on Sesame Street?)
ALK - right there in the video.
ALL - and old man’s dinner is interrupted by an ALL bumping into his floating room. “ALL… ALL!”
EA - an alien tries to hear the echo for his “EA!” sound from atop a mountain, but it never comes, so he shouts it louder and there it is, right behind him!
EE - a monkey finds the two giant E’s in the jungle and chatters, “EE, EE, EE, EE!”
OO - lots of purple extraterrestrials marvel at the sight. “OOOOOOO!”
OW - an astronaut learns why you should never kick a monolith. “OW, OW, OW!”
SH - one astronaut keeps shushing the other, and he finds out why when they see the monolith behind a rock. “SH!”
WAS - two astronauts stumble upon what WAS an ancient civilization, and make another big find in the form of a monolith. "WAS that what I think it WAS?"
And there's one more, but this one's for an entire word: two explorers of the cosmos get the feeling they're unwelcome on the planet they've landed on when they see a monolith crumble into a big, all-caps SCRAM!