Hey, I like that!
One of the future projects is to build another parametric EQ, and instead of re-building the current one with modifications, this design could be well worth exploring to. I first saw the design years ago, then forgot about it completely until you guys talked about it.
And the low+high band go from shelf to bell, that is always good.
Well, got to put this one on the waiting list. Need to speakers.. A passive EQ should be coming up.. NTP limiters waiting to be racked..
EDIT: Bypass on the front panel? Thought you had them in your console. Or have you ran out of inserts?