RTi A1 + dayton audio amp + PSW110

Hello there,

I recently purchased a pair of A1s and a dayton audio APA150 stereo amp. I want to get the PSW110 to drive the lows and i was wondering how I would go about connecting them. Should I connect the line out of the amp to the line in of the sub? or should I use the sub's amp to drive the speakers? Is there a way of making the A1s just take care of the mids and highs and the sub to do the rest? there's no way of setting crossover settings on the amp, so I was wondering if there was another way... this is kinda confusing, I know...

any help is appreciated.