At long last, we finally hear what Brian Muehl's Elmo voice sounds like! WHOOOOOO!!!!!!
Okay, so this is just a short audio clip, not from a Sesame Street episode, but from a recently-uploaded interview with Brian Muehl. Instead of the later Kevin Clash who first performed Elmo by the end of the show's 16th season (1985), Brian Muehl was the first to perform Elmo in Season 12 (1981). Brian Muehl is the grandfather-founder of Elmo's character, and portrayed the character with a high, breathy whispery voice (different from the most commonly heard Kevin's high-pitched falsetto voice). Writers came up with Elmo's character that Elmo is a red monster who tries to learn English or Spanish but would obsess on repeating a word over and over again (i.e. "Casa!"). But the character appears to talk like an out-of-breath panting caveman, and as Muehl states, "Elmo must be a junior version of Animal!" XD
Well, even though some other rare Seasons 12-15 episodes of Sesame Street won't surface, at least we all get to finally hear an audio clip of Muehl doing his Elmo voice.
(unidentified sounds of uproarious applause)
P.S. In the Monsterpiece Theatre "Me, Claudius" sketch from Season 11, that's apparently Jerry Nelson and it IS NOT Brian Muehl doing Elmo's voice in that sketch, just so you know. ;)