Assume you have watched Mackie Master Fader Video on "Home" page,
here is the mixer hard ware that makes it all work.
We use Mackie DL32r & DL1608 iPad WiFi controlled Digital Sound placed close to stage. DL1608 is less expensive if job can be served with fewer inputs and out puts. Functionality and iPad control is same for both mixers.
This is the DL1608 set up for small band. Inputs 1 to 16 are from two 8 channel 50' stage boxes. Phantom power is on/off switch for all channels. Input gain is set with 8 trim knobs. Outputs a1 to a8 go to 8 channel Monitor Amp case for small jobs or can connect to main amp case and monitor amp case. Mixer is covered case housing power module and Apple Airport Express WiFi. iPads can plug into the dock, we have never used this plug preferring the mobility of WiFi. Yes that's me reflected in the screen. My iPhone 6+ also runs Master Fader v4.0
This is the DL32r setup for stage play. Inputs (left side)1 to 8 are from wireless case, inputs 9 to 16 are from wireless individual units, inputs 17 to 28 are from band 12 channel stage box, 29/30 are from iPod with charger, 31/32 are from CD player. Inputs have switched phantom power per channel. Input gain (trim) is iPad controlled per channel. Outputs (right side) a1 to a8 go to 8 channel Monitor Amp case. a11/12 is for subs, a12/14 is for stereo mains left/right. Headphone plug goes to Sennenheiser IEM transmitter for wireless solo listening at FOH. Mixer is in a 4 space SKB case with Furman Power conditioner. Apple Airport Extreme WiFi & IEM transmitter stored in back of case