In the guidelines, it clearly says level +10
However, in the spell, it says equal to level, presumably counting the +2 Voice.
Now, I believe it means base level +10, but a fellow troupe member contests, and nothing was mentioned in the errata.
Level + 10 is for Personnal Range.
So, a level 10 DEO with personnal range would strip 20 might.
A Voice range DEO would be 10 +2 mag = lvl 20, and strip 20 might.
Same thing for a base 30 DEO; strips 40 might at range personnal and level 30, but 40 at range voice and lvl 40.
So yes, it is Base level +10.
Sorry if I'm unclear, i'm very tord, and my neurons are collapsing into oblivion 