In the Alvin and the Chipmunks, The Chipmunks, and The Chipmunks Go to the Movies television series, Karman provides the speaking and singing voices for Theodore, Brittany, Jeanette, and Eleanor. She was also the co-creator of The Chipettes.
In Alvin and the Chipmunks: The Squeakquel, Karman provides the singing voices of Theodore and the Chipettes. However, like Theodore, she does not provide the speaking voices for The Chipettes like she did in the cartoons. Instead, the Chipettes are now voiced by Christina Applegate (Brittany), Anna Faris (Jeanette), and Amy Poehler (Eleanor).
She retains her singing roles for Alvin and the Chipmunks: Chipwrecked.