Not sure about the sound because my HIDs are after-market (McCullochs)
The color is the "color temp" (Kelvin rating) of your bulbs. There are charts online that show you the difference, but I believe that OEM is something like 4800K-5300K - it won't start looking "bluish" like Lexus until you get over 6500K on up but also know that higher temp colors can also deliver less light on the road where you need it too.
