I have to bump this thread, as I'm considering picking up the Avantone CK-1 in addition to my Pelusos. Yes, I know I just stated a few days ago that I'm scared of 4-mic mixes and phase issues. Still am.
So, what would be gained by having these two sets of mics, considering I probably wouldn't be able to split either the Avantone omnis or Peluso subcards? Has anyone run, say, cards/hypers XY with subcards NOS? Or would all this not be worth it for the final mix?
Barring on-stage configurations (and sbd-ambient mic matrix mixes, though those aren't 4mic mixes), what I'm really hoping to accomplish with a 4-mic mix is this: (1) get the "focus" and soundstage detail I find I get with say cardioids near-coincident (or hypers) (2) get the huge soundstage and feeling of spaciousness I get with split omnis. This is what I'm hoping for, though I really haven't gotten there yet. In large part since I most likely will only do this for outdoor shows and I just haven't had enough opportunity to try yet.
My main impetus has been the fact that I just haven't been too excited by my split/j-disk omni 2ch recordings, and I want to capture that omni magic while still retaining the soundstage detail I find with cardioids.
That said, for me, I don't think I'd be happy with omnis/subcards NOS. Just not convinced that'd capture the huge soundstage I'm hoping for -- I'm guessing it might even make the mix tend more towards mono than just a 2ch cardioid near-coincident recording. If split omnis are out, I'd recommend trying j-disk omnis for the 2 channels.
BTW, why is split omnis out? Even a 1-meter split will give you good stereo separation, and this isn't too hard to accomplish with one stand (for all 4 channels). If it is concerns about phasing, using a true coincident pattern for your cards should help.
Also, it'd be helpful to know what you are trying to accomplish with a 4-mic mix in order to comment on whether NOS omnis would work -- I'm just projecting my desires onto your proposed configuration.