Lilo and Stitch Wiki

Frank Welker is a guest star as the voice of Sparky, Sunburned Ice Cream Tourist (2002-2006), additional voices and the vocal effects of animals as well as various experiments.

From the former cast from The Simpsons in 2002.

Now, from the current characters of Soundwave, Devastator, Reedman and Grindor from Transformers in (2009-present).

Since had voiced so many experiments in the original series he decided to voice only one for "Stitch and Experiments" and that was Furry.