need help selecting Oppo

I am trying to figue out what Oppo unit would work best for me in a very modest 2 channel system that would have to use a universal player. Both my space and budget are limited. I now use a NAD L73, all in one unit, but music vocals can be "edgy" so I find myself not listening very often. I plan to replace this unit with a decent integrated amp. Any advice or other products recommendations would be welcome. My speakers are Vienna Acoustic Haydn's.