you are a personal friend of Andy Jones? Interesting.
His install was done in Atlanta GA by Jeff Smith and tuned by Scott Buwalda. He is a serious competitor for sure, although I can be nearly positive that what you would refer to as sub-bass comes from his FRONT mounted midbass’ and his free air subwoofers require a stiff suspension and are crossed over at a nearly infrasonic frequency and are greatly attenuated or simply shut off for any SQ judging.
Most likley they are utilized for everyday listening and for attaining the maximum points for reaching the 130 db minimum in the SQ plus section of judging.