dont think most companys make 8 g speaker wire ,thats where they branch off into power wire. most people who want to use 8g for their subwoofers use power wire. If your talking about running 8g on regular coaxial/component speakers then thats way overkill. For wiring your subwoofers with 8g this would work for you.
well i have 2 fi Q 12's on 3000 watts in a sealed box (until i can design and build my ported box) and the speakers are going through one set of box terminals. would i be able to get away with anything skinnier?
When installs call for 8ga speaker wire, I used power wire. The biggest 'speaker wire' I stock is 12ga. And in 99.9% of installs, that is over kill...even though every box I build that will see over 800wrms gets 12ga direct wiring, lol. (lower power gets 14ga) But for ~$10 extra per box I will run 8ga to anything...that means ~10ft of wire (5ft+..5ft-)
To tell the truth, the only install I have done in awhile that really NEEDED 8ga speaker wire was our van. The 20kw streetbeat machine w/ 10 DD2515's.
8ga can VERY easily carry 60amps. So...think about this...60amps at 1ohm means 3600watts.
Drill a hole about the size of the wire, run the wire thru, hotglue or caulk around it.
I have seen FAR too many box terminals melt to EVER build a box and use them. Even on 300w setups, I run direct wire thru the box to the amp. Terminal = resistance.
i had box terminals on my last setup. one of the little boot connectors fried itself and melted all the plastic around it and disinegrated the terminal tab.
but just putting the wires through the box sounds easier anyway