I keep seeing references to different music formats. What is this all about? I am in search of CD recordings that are beautifully done. I typically listen to them in 5 channel stereo. Is this bad? I am looking for those recordings that have powerful detailed audio. It seems that many, MANY, recordings have the dreaded "hiss" background noise. I am not sure if this is from just poor studios or if it simply because they were done so long ago that the equipment used was inferior. Most recently I have found that Diana Krall's stuff seems to be done perfectly. Are there any other reccomendations? I like anything from Diana Krall to Metallica. I want to use this to show off my system to friends and for personal enjoyment. It seems that every time I show my system to friends they select a CD that is horrible. They are still impressed but I am not. Please give me some answers. I think I have finally grasped the intricacies of DVD but I am a complete newby to audio or CD. What should I look for?