Callier studied image, sound and editing at RITCS between 1990 and 1993. After his studies he worked as a sound engineer for the public Flemish broadcaster VRT. In 1995 he co-founded Hoover (later Hooverphonic), where he is active as a musician, as well as a composer and producer. In 1999 he wrote the music for the Belgian film Shades. In 2000 he received the ZAMU Award for Best Belgian producer.
