Based on the manuals that I downloaded from Sony, you can hook up speaker-level connections to that sub and then run speaker-level connections from the sub to those bookshelf speakers.
The thing that I'm having trouble getting around are the speaker-level connections on that mini system. If I'm reading the manual correctly, it has two sets of speaker terminals per speaker, one for high frequency and another one for low frequency.
I'm pretty confident that I could get you up and running with putting that sub into the mini system, but I'm not so sure about the bookshelf speakers. Well, I know they could be hooked up, but I'm not confident that it would be correct.
So, my questions to you are this:
1. Do you have those bookshelf speakers already hooked up to the mini system?
2. If so, how do you have them hooked up?