adding a sub


i recently purchased paradigm studio 40 v4's. I feel i'll need a sub, possibly 2 small ones. My question is this: my amp has only binding post for right and left channels. My pre only has 1 pre-out. Where do I hook up a sub? If I hook it to 1 channel on either side how does that affect the speakers?amp? I may get 2 small subs just because all of my stuuf has to be symmetrical or I freak out a bit.
sprink
Thanks for all the info. I have found the information on this site extremely valuable.It is a fantasic resource.

Bob, I bought a SVS PBS12 NSD.

I apologize for my tendency to be redundant on some subjects, like this subwoofer, but I just want to get the right thing and hook it up correctly.
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Thanks for your info Bob. I was wondering about that. It says only one cable, but I figured I'd need 2. I am expecting it Wed. I will get everything going and hopefully figure out the meter, I bought one of those also. Thanks again for your information.
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