Left to right, Phase to 0, EQ to 0dB, volume to about halfway, crossover to 140Hz.
Run the auto set-up on the Onkyo, and have a look at the settings it's come up with: should have set all the speakers to 'small' and the subwoofer crossover to 80Hz or so. Manually raise the subwoofer crossover to about 100Hz in the receiver's menu - see manual, p72 - and you should be just about there.
If the bass seems a bit lightweight, try the +6dB setting on its EQ switch, and/or raise the level a smidge using the sub's volume control.
That should do it...