Cooking up subwoofer


I have a simple system naim atom driving focal kanta 2 speakers want to hook up a rhythmic 12" subwoofer. Not sure How to on the back of the atom.I hooked the rhythmic to preamp out on the atom I do get response but there’s not much there. Obviously the rhythmic has it’s on amp so...
myradio
Seems like the preamp out should work. Some of the rythmik subs have speaker level connections. Which one do you have? 

If you have speaker level connections Tee-Jay on YouTube can show you how to do it. He's awesome!

https://youtu.be/Ew7G6H9YoVA
I use modified Rythmik plate amps.

Gain and Xover.

Set the XO at 100 hz or so (should be less 60-80) and the gain to 12:00 or so.. READ the manuel, and fine tune it..

Placement, for your listening position, is key, not everywhere else.
One servo unit, is better than most. I really like um..

Got to break in, too.. takes 50-100 hours or so. 

Enjoy..
Thanks gentleman the problem is solved I threaten to stuff it with dressing and Cook it in the oven and all the sudden it works fine now. Actually what happened I believe is  I rebooted the Naim by basically unpluging it and plug it back in, It worked not sure why I'm not even sure that was the answer because I did  trace the wires hook ups But they were correct so I'm not really sure but nevertheless it's good to go And yes I do read the instructions yes I do know it has a volume and switch thank you guys Somewhere very helpful. Have a happy thanksgiving.