connect sub woofer from preamp out on integrated?

A newbiew question. I would like to enhance bass to my 2 channel system by adding a sub woofer via Preamp out from my integrated. Is there any problem with that?
I'm doing the same thing. Do I just need "normal" RCA-type cables?
I'm connecting a Vel' Optimum-10 using the preamp outs from my Cambridge Audio Azur 840A II. They look like normal RCA outs. Or, is there some sub-specific cable interconnect I should be using? Advice? Thanks in advance!
Oh.. My mains are Heresy III's, not sure if it matters. If anyone has similar experience, I'd love to hear starting points for x-over, et. al.
Thx again for providing thid info. I probably need to re-think this system. Fortunately it is a second one.
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Indeed, that is very helpful. My Epos sub has hi and low level inputs/outputs (with a variable frequency cut off filter) and I think I am starting to understand what needs to be done....unfortunately, the Classe CAP 101 has pre amp out, but no Amp IN jacks....could I use the Tape IN jack instead of an Amp IN? Thank you for your patient guidance.
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yes, I am running the Gallo speakers full range....plse explain what bass management means.....thx.....
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Thank you Bob. I have a Classe CAP 101 integrated amp with preamp out and an Epos sub woofer. I also have a pair of Gallo micro Ti speakers that don't do the low frequencies. Wanted to make sure I can't damage any components by feeding sub from preamp out. In the past I have connected the sub to a home theatre receiver that has a dedicated sub woofer single cable output. The Classe has a 2 channel preamp output, of course---is only one cable required to drive the mono sub or should I connect both preamp outputs to sub? Much obliged for assistance.
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