These are hung line arrays no ifs ands or buts. The difference between this and the Vertigo outdoor show is that the vertigo show had huge cabinets that hung bass and treble, but it was more of a wall of sound idea versus line array. With line array you have many more smaller units that can be hung in different configurations and as each unit is wedge shaped in the back, each unit's hang angle can be adjusted within the line. Coupled with their modelling software, the sound team will be able to model this sound much more precisely with smaller units in more abundance. They will also be able to tweak the sound on a stadium to stadium basis more finitely than they were with the big cabinets. If the upper decks are steeper, higher, flatter, more absorbant or reflective all calibrates into how they units are mixed, and even physically how many units are used and at what angle. I would argue that we may actually see these lines change in size and angle depending on the size of the venue they are playing in.
I would bet that they are Clair Brothers as CB has supplied every U2 tour since the beginning. I coauld not find the exact model on their site, but if I had to guess I would say this is their CAT214 system with custom grilles:
Since almost every major audio company is now manufacturing touring line arrays, I have to imagine Joe O'H commissioned these from Clair and no one else. If he did go elsewhere he probably got them sourced from L'Acoustics (as they really are the ones who pioneered line array with v-Dosc) and they are probably part of their K1 system:
What I find interesting is that he has not hung seperate subs over the horns and the rest of the cabinets. They look like they are the same cabinets from the bottom of the hang to the top. I think he actually hung the subs down the outside edge of each hang with the mixed units on the inside. Moreover, from this photo I think the base of the stage is lined with subwoofers which means high high tones coming down from above, and the lows spreading out across the floor:
From the pics it looks like there are approximately (18 mixed cabinets x 2 lines = 36) + (18 subs x 2 lines = 36) = 72 cabinets per hang. Multiply that by 2 for each North and South side = 144 cabinets per side x 2 = 288. For the East and West sides there are 16 mixed cabinets and 16 subs per hang x 2 per side = 64 per side x 2 sides = 128 cabinets on the East and West. So N, S, E, W = 416 Cabinets hung above the stage. There also look to be 40 subwoofers under the stage.
I do not think there are any cabinets under the catwalk, but I would not be surprised if there are.
The delay towers look like they have 8 cabinets each.
So total without catwalk - I count 472 cabinets which is a huge amount of sound.
The most interesting thing out of all of this is that Joe O'H really has a much much more advanced toy to play with than ever before. Forgetting that they are even using line array for a second he is doing so in 3 dimensions. He has obviously done this in every arena tour, but to be able to model his sound in stadiums at this scale is amazing. Rather than just pointing the boxes out from one end of the stadium with some delays and different angles, he will be able to model what each side of the stadium will hear prior to each show as he has such control with so many units and locations.
Enough nerd speak.
This is going to be fucking loud.