Thanks to all for giving me some great guidance as I completed my basement with prewired home theater.
I had the foresight to install Zone 2 wiring that leads to an outdoor space that will run from Onkyo TX-NR818 with 14AWG 2 conductor speaker wire (one pair).
I just installed 2 DefTech AW6500s aimed toward the pool. I like them so much that I want to add a second pair over a 500 sq. foot deck.
Unfortunately, I've only got 2 speaker wires prewired that lead outside. Without having to tear up some drywall I would have to add these 2 additional speakers in either series or parallel with my existing speakers. (DefTechs are 4-8 ohms). I would like to keep the circuit at 8 ohms. (TX-NR818 goes down to 6 I think).
Any thoughts on how to best configure this? All 4 speakers would be mounted against the back of the house aimed to the back yard.