My church has a convention centre that can seat up to 60,000 people. And they have 8-10 roof-mounted Peavey speakers every 60 feet. I think the entire convention centre has over a 100 Peavey speakers. The core team who sit within the main control room consists of 8 members. Then they have about 15-20 members in teams of 3-5 managing the smaller relay units. Then they have a third team that is responsible for lugging equipment and being the "spotters".
Guess what the coolest part is? My late maternal grandfather had designed and overseen the construction of this convention centre.