Use 'clamour' to describe very noisy situations where many people are talking or shouting at once. The clamour of excited fans filled the stadium after the goal.
Pro Tip 2/3
Increasing Volume
Indicates the volume escalates as people try to speak over one another. The classroom erupted into clamour when the bell rang.
Pro Tip 3/3
Lack of Clarity
'Clamour' suggests confusion and difficulty in discerning individual words or sounds. Amidst the clamour, I couldn't hear my own thoughts.