One of my favorite concerts ever is Chicago with Earth, Wind and Fire at the Greek Theatre. This isn’t your standard, 4-piece band setup. Instead, it’s two rock bands with two horn sections, with many instrumentalists doing double duty as singers.
They have tons of changes with who plays/sings what, and two large bands on at once for much of it, so it’s pretty convoluted. There are more or less three levels of risers, which really helps to keep zones separate, visually and sonically. The two drum sets are on the back corners, with two keyboard players between them. There is a third set of keys in front of the left drummer. The key players also sing at times, with the Chicago player singing with a head worn mic. The other two keyboard players have mics on stands for singing. There was also a percussion set on the stage at one point. There are many handheld mics for singers to pick up here and there. Many band members switch often between their main instrument and others (usually tambourine and singing as the second/third thing they did).
It seems most, if not all members have a single in-ear monitor. Despite this, there are six wedges on the front of the stage. Between the many guitarists, they have a full stack, and at least three other amps. The EW&F bassist (founder of the band), is definitely wireless, since he loves speed walking around the front of the stage, full-time. The left drummer has two amps, and at least one key player has at least one dedicated amp. At least one guitar amp was single mic’d with a non-SM57 dynamic.
The six horn players all have clip-on, wireless mics. It looks like one drummer has small-diaphragm condenser overheads, and the other one chose large-diaphragm overheads. I’m sure they both have many additional drum mics as well. Without going into every detail, that’s’ the basics of the setup. You have to watch it, and look up images from the show to get it all in. If you’re not going to watch much, go to the end of the second video where the bands play together again and watch to the end (1:03:30 to the end). Set changes alter everything; in the last one, there are six drums sets (it’s better to just enjoy it than try to keep up with it all).
The key for this stage setup is to maintain the overall vibe on stage. The performers fully sell the novelty of having them play together, often moving around each other and removing their in-ears so they can really get some synergy working.