12 gauge is good for up to 100ft runs IIRC, so you should be good there.

These will work for the sub splitter

http://www.monoprice.com/products/produc...=1&format=2

or

http://www.monoprice.com/products/produc...=1&format=2

I think this might be the TRS adapter you are looking for

http://www.monoprice.com/products/produc...=1&format=2

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70