Wow, two explanations, but not any clearer. But, I think I get it. Unfortunately, original poster is unable to communicate his needs. I suspect he has bitten off more than he can chew. He is talking about wiring the walls of his room for 5.1.

He is talking about connecting one of these...
http://www.outdoorspeakerdepot.com/wp20tespse.html

to one of these...
http://www.outdoorspeakerdepot.com/sispbipo.html

It is not clear whether he has figured line level from speaker level yet, hence the perceived need to solder. He is attempting to connect a line level input on the 5.1 plate to the speaker level output plate.

Also unfortunately, I have no advice for him. I wired the walls of my HT prior to drywall. If you are using solder, you're probably doing something wrong.