Sub-woofer connection

I have a sub-woofer and I want to change my current setting. But I am not sure that I will blow my amplifier.

My sub-woofer has two types of connections:
1. via banana plug - mono output from the integrated surround sound amplifier to the mono input of the sub-woofer.
2. via the standard speakers connection i.e. the right channel +/- (red and black) and the left channel +/- (red and black)
Right now, I connect my amplifier with the sub-woofer via a banana plug. When I play it, I need to turn on both amplifiers, (the amp and the sub-woofer built-in amp).

Currently, I bought a new surround processor which has a sub-woofer pre-out to the power amp via interconnection cable.
I was wondering if I use an extra power amplifier to make a connection from the pre-amp -> power amp -> sub-woofer, can I connect the power amp via its left +/- and right +/- to the sub-woofer's left right +/- ? Do I still need to power on the sub-woofer built-in amp when I play them? Thanks!
Dude -run from the LFE out on the surround processor directly to your subwoofer in. If you have L&R inputs check the manual to see if they recommend using one or the other or if you will need to add a Y.

While you have the manual open, check to see if your sub has auto-sensing - meaning that it will turn on automatically when it detects signal and go back to standby some number of minutes (varies by mfgr) when signal stops.

Do not add an amp into the loop as there is no way (and no reason) to bypass the amp in most powered subs. Nor are most amps up to the task of handling a sub.

Good luck