I have a three-stack per side of the 12" servo woofers in open baffles. I find that getting the settings right on the A-370 PEQ sub amps to give me an optimum results very much an iterative process. I concocted this diagram to help keep me track of what iteration I happen to be on now, and which combination of controls has given me the best results so that I can go back to it easily. I have spent literally hours moving the subs around and making control adjustments. It is very easy to get lost doing this.
I hope this helps you; it certainly helped me.