Audio engineer. Hirotsu worked as an an engineer from 1980 to 1991, primarily at studios in Los Angeles and San Francisco, California. Studios he worked at include [l304319] and [l292625]. He then worked at Siemens Audio, teaching digital audio editing and mixing theory and operation. Hirotsu moved to Hawaii in the 1990s and now works as a media producer, creating audio and video programs with the company Issei Productions.