Breaking Benjamin was a sonic mess when I saw them. Sounded like someone stole all the treble and mids out of the PA. Completely incoherent and lots of feedback between songs.
Now, that could be because I saw them at the Electric Factory, which wasn't the best venue. No one was happy.
You gotta get high up the food chain before you can specify a sound system all the way down to the nuts and bolts, or travel with your own that can do big places.
Before that, along with the usual stage chart and wire feeds and stuff the mains system just be specified by some calculation of power and speaker output or just capable of X db at wherever, mix position, back of house, etc.
Or just whatever the house system is.
You got your own sound crew but they might be working with completely different or unfamiliar equipment one night to the next.
Can work out the major kinks with good communication pre-show and time for fiddly soundchecks but that doesn't always happen or little details that can snowball into big problems get left out, etc.
The good soundguys can roll with that on the fly and end up with something at least decent if not the greatest.
The not so good ones, or just inexperienced ones not so much.
I remember seeing a sound contract from Boston. It specified the music bed had to be like 10 or some significant db level anyway below the vocals.
Meaning vocals way more prominent. They could do it like a bunch of trained chiorboys and didn't want somebody washing it out with a wall of ear bleed guitars or howitzer level kick drum.
Thats why theyre the best sounding rock band I've ever seen in an arena. In that case the old Alamo dome. They know how stuff in there keeps rolling and piling up on itself and turns to shit and they put the kabosh on it before they got there.