new cd player or old

Hi-I am trying to upgrade the sound of my cd source from a horrible old toshiba dvd player-I have about $300-500 to spend. What gives better sound-a quality used cd player from 10 years ago, or a new NAD player? Thanks.
HI-Thakns for the suggestions. I purchased an NAD and I am really surprised how much better it sounds than my old unit-right out of the box. Recommended for anyone thinking of an inexpensive cd player.