My findings using an spl meter.
Did a manual calibration using a manual silveline spl meter. The settings I used were C weight and slow set to 70 db as recommended on this here forum.
Speaker distances FL and FR 4.10m centre 3.61m sub 3.61 surround L 2.69 m and right 2.56m. This set the speakers to FL +1.0db and FR +1db centre +3.0db and SR +4.5db and SL 4.5 I left the sub at 0 (for neighbours sake) all for 75db on the meter.
Cross over all at 80hz when I did it.
Can't help think that these measurments are wrong though at the rears are a lot close to listening position but are a lot louder than fronts.