audio research sp-10

hi..i'm fairly new to tubes. i have an AR sp-10 pre, AR d-125 amp, vandersteen 2ci speakers, and a shanling t-100 cd player. running the cd player on the tube output of the shanling. my music tastes run the gamut from synthpop/techno...to sarah mclachlin, and josh groban. the system seems just a tad bright to me, which it seems it shouldn't with all the tubes i'm using. i've put the sp-10 on "high gain" which seems to help...is it "bad" to use the high gain on a regular basis? also..my speakers are biwired..but with no name wires..any suggestions for compatable speaker wires and or interconnects (using legend interconnects right now) or any other suggestions would be appreciated. thanks in advance :)