My Onkyo TXSR-703's auto setup/EQ set the L/R Sierras as small, and the crossover was set fairly high, even higher than yours I think. I reset everything to 80Hz(THX) in the setup menu. I have tried the Sierra's with a 60Hz setting but I could not tell a difference in casual listening. I am using a UFW-10 sub which is pretty tight and musical, so it blends in very well even at higher crossover points.
Ed
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