Pat Fraley is a voice talent and coach who has voiced more characters than any other actor.See Episode 21.
Anne is a VO coach and voice talent who also hosts the VO Boss podcast. See Episode 48.
Dave Fennoy is well known to gaming enthusiasts, and has a long line of credits. See Episode 32.
Celia Siegel is a branding expert working with voice talent on their brands and web sites. See Episode 53.