As a SQ competitor and World Champion, I can tell you the "real" definition of SQ. It's a judgement of how accurately the system reproduces the music. The goal is to make the car sound as close to the real performance as possible. If the singer was standing center stage during the recording, they should be out in front of you and center in the car. As for subs, it's not as cut and dry as some people make it sound. I have the IA Flatlynes in my car this year. They have plenty of output, but more importantly, they are extremely accurate. A deep bass guitar sounds like a deep bass guitar, not a boom. A concert bass drum actually sounds like a drum, not just boom. In my car, you can actually feel the bass guitar string, the impact of the mallet on the bass drum, the edges of a thunder clap. It's truly something you have to experience for yourself. I switched to the Flatlyne during my search for a sub that could reproduce bass below 20hz and do it with accuracy and realism. Below 20hz is more about the "feel" than sound. The IA Flatlyne does the job very well. There was a Money round SQ competition this past Sunday in Nashville TN. "The Vinny". Two of the top 3 cars were running Incriminator subs. Mine being one of them. It's safe to say Incriminator Audio is gaining ground in the world of SQ compeition.