Pre-Amp Output/Input and Splitters

If I use a splitter from a DAC from my AV equipment how much is the sound reduced by going through a splitter? I started with the Radio Shack gold ones, but now have the AudioQuest ones. (For all I know they are the same splitter.) I've heard stories ranging from 'you won't notice the difference with one spliter, but do it twice and then you're causing problems' to 'OhMYGOD!! Horrible! Throw the whole system away before doing that'.

Of note is that the splitter will be between my BluRay Player and other AV equipment and my 2-channel dedicated Supratek Pre-Amp. What I mean by this is that the sound won't be quite as critical-listening as from my 2-channel CD player. But I do listen to Jazz and Classical BluRay DVDs, and there is a new BluRay music format coming, so I do want to keep it extremely good.