My Live PA experience is limited, i have to admit, and i wouldn’t presume to make any kind of judgement call or criticism about Professional live sound practitioners.
However in the more modest area of being ‘the bands PA guy at small venues i have concluded the following about this particular ‘strand’ of audio work
It’s bloody difficult to get any semblance of ‘balance’ in the typical cramped situations and typical not-that-flexible gear supplied or that its possible to fit in.
Most musicians ( and i speak as a drummer having been in bands, so this isn’t a ‘musicians, huh’ type of comment ) are just like the cliche – they all want themselves louder or else want foldback of the other musicians fed louder to them than to everyone else, which means levels keep going up and/or their opinion of you keeps going down, because you’re trying to do what the SOUNDmans job by not feeding an incoherent and mis-balanced cacophony to the audience, or not enough volume overall for them to hear properly, and no feedback.
Meanwhile the Band want themselves to sound audible aross the board to THEM on stage, and something has to give, at least in small venues it has.
Having said all that i had the ( relative ) pleasure, the last time i did a bands sound a couple of years back in Doha, of using the bass players iPad to remotely control his Mackie DL1608 mixer that all their PA fed through.
The concept is great, assuming one way it’s meant to be used is how i used it, which was doing the soundcheck and adjusting the levels during the gig while standing out in the audience area !
Not perfect, depending on those foldback arrangements and whether they are all controlled by the mixer and so controllable from the iPad, but if nothing else it means you don’t have to keep running back and forth to hear the result of any ‘tweak’. Also not perfect in that any band with more instruments or mic sources than i dealt with on those occasions would be tricky to mix without scrolling between app screens on the iPad, but overall it was effective. The only major deficiency as remote control per se is that of every touch-screen control; there’s no tactile feedback so to make any adjustments you have to be looking at the screen, whereas of course it’s possible to ‘ride’ the faders on a physical mixer while also keeping an eye on what the band are playing.
Having said all that, as soon as i’d used his setup, i decided that when i’m ever in a position again to buy stage-sound gear, i’m definitely buying a mixer that is controlled over wifi from a tablet and can therefore sit on or close to the stage ( for shorter safer cable runs )
Such a setup needn’t be incompatible with also recording performances, as several of these mixers also have multichannel recording to usb storage !