What triggers a vibration from Buzz? How far away can sounds be and still trigger a vibration?

The sound's pitch, loudness, and Buzz's sensitivity level determine if Buzz will pick up a sound. You can change how sensitive Buzz is by using the PLUS and MINUS buttons. If you want to feel everything around you, increase the sensitivity to level 3 using the plus button. If you want to feel fewer sounds, lower the sensitivity to level 1 using the minus button.