Hi Def Music Question

[G-money]

After christmas i will have a pretty nice HT setup and I'm looking to expand my blu ray collection into music as well. Ive noticed it's hard to find good concerts on blu ray and I have a ton of music on my computer, my question is how do I know if my computer music is "hi def", most of them are 320kbps, is that as good as it gets? If not how would I go about acquiring the highest quality possible if they songs haven't been released on blu ray?

I'd like some concert DVD's but not if they aren't the best quality audio possible.