Hey, In Ears seems to be a very popular topic so I thought I would share the system that I have set up for my band. The feedback from the other members has been really positive and after a month of tweaking I think its pretty low maintenance now..
I have a MOTU Traveller MKIII as the main interface which I then connect a Focusrite OctoPre via TOSLINK to provide additional balanced in's.
I have four vocals going into the XLR In's on the Traveller with Bass (2 x MarkBass F500), Drums and Rhythm guitar connected to the OctPre. The guitar is connected via a Behringer Ultra G 100 cabinet sim out of the pre-amp (EVH 5150 III).
The lead guitar connects into two 1/4" connections of the Traveller out of the amp sim on the Marshall Head.
I have Main Out 1 & 2 of the Traveller that I leave for use as a Main Out for recording and then set up 4 stereo outs for use with the IEM.
The whole thing is controlled with the CueMixFX software that comes with the MOTU products. From this, I can set up 8 separate mixes, one for each band member plus one for input into Pro-Tools for us to record shows or rehearsals.
CueMixFX is fantastic. The built in Compressor and EQ are superb. I have put some compression on the vocals to bring them up in the mix and I have used the HPF to cut out some bottom end noise. These really tighten up the sound.
The really cool thing about the set up is that once the config from CueMixFX is saved to the Traveller, there is no need to have my MacBook connected unless I want to record. Not necessarily good for FOH work, but as the ear mix doesn't change much it is a great "set and forget" thing.
The whole system fits in a 2U Rack, but I have installed a couple of Wireless Systems so have it in a 4U. Still pretty compact. There is an iPAD app that can be used to remotely control CueMixFX if your laptop is running which means that I can control a mix from my mic stand if I need to. Or the other members can control their own mix if they run it from theirs as well.
The only other thing I have done is to get a Stage Box and Snake. The Stage Box has a splitter in it as well, with two snakes (one is removable). I have one snake to connect into the IEM system and the other one is used to provide a separate signal to the FOH if they want it.
I really like it. The sound mix is just like being in a studio, plus we get the opportunity to multi-track record whenever we choose to.
The picture shows my bass rig on top of the IEM rig at rehearsal.