Cartwright's normal speaking voice is said to have "no obvious traces of Bart". The voice came naturally to Cartwright; prior to "The Tracey Ullman Show", she had used elements of it in shows such as "My Little Pony", "Snorks", and "Pound Puppies". Cartwright describes Bart's voice as easy to perform, saying, "Some characters take a little bit more effort, upper respiratory control, whatever it is technically. But Bart is easy to do. I can just slip into that without difficulty." She usually does five or six readings of every line in order to give the producers more to work with. In flashforward episodes, Cartwright still provides the voice of Bart. For "Lisa's Wedding", (season six, 1995) Bart's voice was electronically lowered.