I have 170's and tried different crossovers with my Outlaw 1050.
80 and 100hz were virtually identical, and 60hz left a noticable hole in the frequency response. I have it at 80hz with no problems.
The crossover is not a brickwall.........response rolls off from that point. Linkwitz-Riley crossovers have a filter slope of 24db/octave.....meaning the spl at 20hz is 24db less than at 40hz(an octave above a given frequency is double that frequency......someone correct me if I'm wrong).
I'd leave it at 80hz.
Ed
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