Aspect of the falcon + Improved critical

[Sotnik]

Hi! Could you please advise if Aspect of the falcon (Ranger spell) can reduce crit range of a weapon from 17-20 tp 19-20?

Aspect of the falcon: the critical multiplier for your bows and crossbows becomes 19-20/x3.
https://pathfinderkingmaker.fandom.com/wiki/Aspect_of_the_Falcon

[mbradtke]

i dont think it stacks but i never tried it, however, usually stuff that inceases the crit range doesnt stack unless it is said so

[climbingeastofwinter]

Based on how it reads I would assume that Keen/Improved Critical would work with Aspect of the Falcon to provide a 17-20/x3 crit for the affected weapons, but that is just speculation.