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The Recording Studio is seen in The Muppet Show episode 313. As Kermit announces, Helen Reddy "swings up a storm in the Muppets' private recording studio." There, Reddy records "Blue" with The Electric Mayhem.
Two sound engineers work from a control room, one of whom is identified as Roger. They observe that Animal's levels are a bit too loud. They attempt to communicate to him that he needs to tone it down, but Animal is oblivious. One of the technician's ears are damaged from wearing the headphones, and he is treated later in Vet's Hospital.