Okay, I'd like to try a color shampoo enhancer (probably John Frieda), but I'm a little confused as to what color I should get. My hair is a dark auburnish color. Do I buy the shampoo for red or brown hair? I used to use the Biolage color enhancing conditioner in copper, but it REALLY brought out the copper in my hair. I don't want my hair to be really brassy, but I want there to be a little more dimension in my haircolor.