I also run my 805's full range, with a REL strata III sub, and am very happy with my Harmonic Technology Pro9 Plus bi-wire cables. Their is enough controversy and plenty of hype in the cable business, but the overwhelmingly positive reviews (Stereophile, Absolute Sound, etc.) of Harmonic Tech's line is on the money in my experience. Maybe starting with a better quality ("single crystal") material makes the real difference, I wouldn't know. They are still reasonably priced, and do show up at Audiogon for about 60% of their retail price. DH Labs do make a good quality product for the money. I use their cable for my sub, but they are not in the same league as H.T. The 805's deserve the best you can afford.Haven't heard the Valhalla. Good luck.