I'm not talking about when characters change performers and such, I'm actually talking about characters who have had the same performers from the first time we saw them to where they are today... with some, even though they've retained the same performers, sometimes their voices still change over the years, whether because the performers change it themselves, or because their own voices change with age. Which characters' voices do you think have changed the most over the years? Others not so much? I'm not so sure I'd include Big Bird on the list, considering his voice change was a conscious decision, since Caroll decided it would be best if Big Bird was a kid, rather than a bumpkin... now Oscar on the other hand, that isn't such a drastic change, but I do feel his voice has improved over the years, and as Caroll's gotten older, it seems to suit the character a bit better, not to mention his story about the cabdriver who inspired his voice, it's a much better mental visual seeing the cabdriver with Oscar's later voice, as opposed to his earlier voice. I think perhaps Gonzo has had the most drastic voice chane over the years, though to be fair, I know Dave wasn't entirely comfortable with doing voices (but then again, neither was Frank at first): listening to Gonzo from Season One of TMS and Season Five is quite a difference, just as listening to Gonzo from one of the earlier Muppet movies and one of the more current movies is a bit different as well. Frank's Grover's gone through some less drastic changes, same with Bert: both of their voices seem to have gotten a little higher over the years, then a little lower again in more recent years; Frank's current Grover doesn't seem quite as raspy anymore either.