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?
yes, I am running the Gallo speakers full range....plse explain what bass management means.....thx.....
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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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Thx again for providing thid info. I probably need to re-think this system. Fortunately it is a second one.