When I first watched the animated series, i remember thinking wow that's a seriously tough voice for batman...because up til then all we had was the Adam West suaveness, superfriends version and Keaton's whispery gravel, which was fine, but not memorable.
For me, Kevin Conroy's Batman is as schema-reinforcing as Mark Hamill's Joker...the quintessential versions.
There've been others who've done a great job, but man oh man, if you haven't watched at least Mask of the Phantasm, you're missing a great Batman story....
Almost as important as James Earl Jones' Vader ( of course he was the original voice), but Conroy almost wipes the slate clean with his version of Batman.
What's most interesting to me is Kevin Conroy's story....he had it rough emotionally growing up, not unlike a young Bruce Wayne and he identifies with Batman's heartaches etc and it shows...he's a wonderful actor.