Hi Slide, since you know your way with the mixer check and the Soul’s are new (nice quiver!.. my son would like a 8 too.. we are missing that one..
) you could do a short mixer test just to check.
Perhaps it was just not enough wind for the 10 and it needs bedding in, try the 12 next time..
In steady wind it can be easily parked overhead without overshooting.
if you use a FS bar I suggest you take the line extensions of it for the 12, we like the steering much better that way (twintip and foiling)
Since I got some Peak4’s I did foil only once with the Soul 6m.
Were you also a member of foilforum in the early days? Do you also Kitefoil? If not I would suggest that too.. you have the best Soul quiver for that..
it is very rewarding when succeeding in it.. very Zen feeling when flying the waters and much less physical for the body.
I see you posted while I was typing..
Check the vid of Armin Harich in which he explains the (long) mixer check for the Souls.
Z is not that important but you should Aline A and Z first. I do that with 2 screw drivers in the tiles, about 10 cm apart, one for frontline and one for back line briddle. Than tension A and Z and Aline them by stepping side wards.. if they line up then check B and C under tension.
I hope you understand what I mean..
If right and left are oké then fly it. (If you check left and right C main briddle they are probably the same length from pulley till end)
If it is not flying like you want, tip collaps the main issue, the take the 2 C-mains and shorten first one C 1-cm and then make the other C- equal again. So you can do easily and Quick adjustments without complete mixer test on the beach.