I worked for Rogers Sound labs in so cal and yeah we put in mostly home speaker components from thier line with hand would cross overs and filters it was a cool time to be in that field that was still into cassettes the new tech moving from 4 and 8 track
he did suggest taking the midrange speakers and put them out of phase with the woffer ant tweeter. seemed to calm down the midrange bulge
I heard Stevie Wonder called him to hire him for sessions, and a tour, but Parker hung up the first time, because he didn't really think it could be him.