I liked Bloo's voice in the earlier episodes!

[Mr. Marshmallow]

I honestly am glad Bloo's voice changed and Mac's as well. In truth, this is something you commonly see on TV shows. When a show begins it takes voice actors time to "find their voice" so to speak and see which voice works better and how to improve it.

Frylock from Aqua teen Hunger force had a similar problem. Watch the ATHF's first episode and you'll see Frylock's voice is very different then what it is today. I love Bloo know because he's really perfected that sassy, giddy screaming maniac that he's become today.

But in truth, Mac's vocal improvements are much more admirable. In the beginning Mac kind of sounded like either a tomboy girl, or younger then his actual age in the show. By the time Mac's actor got it right, Mac sounded great and he especially provided some kick ass "wild screams".

Like in "Squeeze the day" and "Bus the two of us".