SQ is an acronym for Sound Quality, which is not limited to one single brand, Focal, although Focal makes one of The Best SQ Speakers in the entire world, yet there are other brands which are Sq oriented as well, such as Morel, dynAudio, Rainbow, DLS, even pioneer PRS line up stage 4 etc (for speakers)
SQ is not limited to only speakers, it is everything collective, from HU to Amplifiers to Wires to processors. Some top of the line HU manufacturers in the SQ industry are Denon, Clarion, Alpine, Pioneer Stage 4, McIntosh and a lot more. Same is the case with Amplifiers Adcom, Audison, Brax, Sinfoni, McIntosh.
SQ and SPL are two different things, you can add good speakers and amplifiers to your setup but its pretty simple, a thing would do what its supposed to do, a simple example is of a Hybrid car, which is meant to provide you with economy, not meant to run on the track. Although no harm in running it on the track, but it wont be able to do what its supposed to do.
