Originally Posted by jebise101
will that make much of a difference, because i doubtfull they will upgrade to 12. Am i better off getting bestbuy to do it later?
PS bestbuy would be cheaper too, just wanted the builder to do it before the walls are up to make everyone's lives easier.
See this chart
for recommended wire sizes based on speaker impedance and wire length. It will always be cheaper AND easier to run wires before the wall is finished. The price difference between 16g and 12g should be minimal for just a few runs. The majority of the cost will be the labor and the labor is the same regardless of the wire size. If your contractor won't provide the 12 gauge wire, just buy it yourself and give it to them to run instead of the 16 gauge.
It is always preferable to make permanent things like in wall wiring capable of handling future upgrades. Sure, you have a HTiB speakers which most likely are 8 - 16ohms, but who's to say you don't decide later on you want a full blown theater setup and the speakers you want are 4 ohms. In this case 16g may be too small a wire to carry the signal without degrading it. Keep in mind speaker manufacturers only state the nominal impedance. Actual impedance can drop VERY low depending on frequencies. I know some Martin Logans will dip down below 1 ohm even though they are 4 ohm nominal.
Will it make a noticeable difference? YMMV. It all depends on you and your setup. For basic movie listening at moderate volumes in a room with poor acoustics maybe not. But once you start moving up ladder in terms of quality, you will start noticing insufficient wire sizing.
Note that I said sizing and not cost. Any decent quality wire of sufficient size will work. You can get it from any 12 gauge stranded wire from your local hardware store or eBay. Last time I checked eBay it was less than $80 shipped for a 500' spool of 12 gauge. It doesn't need to be name brand.