I can't help with what you are asking for but you have be curious.
What type of problem is he having? I had some issues with the subs on my Super Vs also.
His issue is not having the bass levels that he is looking for.
This is a pretty unusual situation with Super-7's as they have the ability to really hit some high SPL levels even down to the rock bottom. Most people can't stand to play them loud enough to work the woofers too hard. Keep in mind these have four 12" servo subs.
However, he feels like the bottom end is maxed out and won't keep up with the levels he is playing the upper co-axial driver. It is possible that he is playing them really loud. That P-Audio co-axial will handle a ton of power and play at insane levels. So the servo subs could run out of steam first, but that would be really loud.
We have removed the shelving circuit so the woofers won't have to play as low. They now have a lot less excursion demand. But he is still driving them hard enough to run the amps into thermal overload on occasion.
So we need to determine if there is an issue or if his preference might be a bottom end that is 10db or more above the rest. A room response will tell us what he has and then help us get him what he is looking for or solve his problem.