<font color='#000000'>Assuming you have a modern receiver, send the 'sub-out' to the sub via a single RCA audio cable and put a RCA male to female Y-cable on the sub inputs.
Set your main speakers to large, but if the low end is muddy, you may want to set them to small, so the low end is sent to the sub. Of course, the CHT-12 is an efficient speaker, at the expense of being a bit muddy - but OK for the price.
I haven't heard the Klipsch speakers you have, but they are rated to go to 37Hz +/- 3dB
Yammy's recommendation on the crossover is dead on... you need to sweep it to find the best blend. If you have a DVD like Star Wars, you can use the THX optimizer located in the setup to run a sweep frequency to set the right crossover.
Enjoy your system!
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