Here is the full list of all 11 Noise-o-matic achievements.
Play your first soundboard sound.
Upload a sound to the Steam Workshop.
Play sounds 10 times.
Play sounds 100 times.
Play sounds 1000 times.
You have shared 10 sounds with the Steam community.
You have shared 100 sounds with the Steam community.
You used the realtime voice changer!
You used the audio recorder!
You recorded 60 minutes of audio!
You played audio for 60 minutes!