I have been using Mogami W2941 for the longest period of time.These cables are constructed of eight conductors.If configured as a stereo pair (4+4)they equal 10ga.I use them as 30ft.internal biwire which equals 13ga.at the spkr.end.I recently compared them to a 35ft.$4000.00 pair of MIT biwires and sold the MIT's they're that good.Other good choices from Mogami are the W2916(6 cond),and the W3104(4 cond).Many sources to purchase from,and reasonably priced.W2941 is around $7.50ft.W2919 $5.80ft.,and W3104 $4.07ft.Excellent value,used by many recording studios.
Long Speaker cables
I recently moved my system from in between my speakers to an adjacent wall. I didn't expect the sound improvement I got. Problem is I had to do away with my 10 foot Synergistic Research Tesla Accelerator speaker cables and I'm using some bulk 10ga, Blue Jeans cable at present. Sounds good but I know there is room for improvement. Are there cables that are better suited for longer runs? I need 25 feet.