SparkE!
try tucking the mics tighter to the disc face,... it'll "widen" the sound out more for you.
this isn't speaking to your timing or phase issue of 4 mics mixed, but rather, as a solo stereo disc recording.
Yeah, thanks Moke, but the ones I'm running are actually set up like boundary mics, mounted flush with the surface of the baffle. I think that the issue is that the faces of the baffle point in directions that are only 110 degrees apart, rather than at 180 degrees apart like a jdisk. The whole idea was to create an ORTF-like signal that has some bass in it. I get a good bass signal, but there is less separation in the channels than on a jdisk setup because the faces of the baffle are both faced partially forward, not straight to the sides.
You are right that with a normal jdisk, you can widen the image by mounting the mics closer to the disk.