The diagram looks a bit complicated because it has been designed to listen and compare many possibilities :I (we) need very careful look on it for understanding what's going on and what you can do with the QSys configurations! I fell it would be almost impossible for me to fully understand it by the single diagram you shared, though; I will further try to "read" the diagram.
- without/with FIR/IIR EQ for front/subs/surrounds
- compare various EQ
- switch between music and movie (X-curve) together with LFE level at +10dB
- compare 1/2/3/4 subs
- compare real central loudspeaker with phantom center
- listen independantly each channel or speaker
- add a tilt curve, inspired by Quad preamps
-....