Composer, arranger and keyboardist, born 30 January 1975 in the Netherlands.

Spierenburg has written and arranged music for several (international) artists, TV series and games. He joined Within Temptation in 2001, shortly after the release of Within Temptation's second full-length studio album, Mother Earth.

Spierenburg co-wrote songs for various Within Temptation albums, including Angels, Memories, Jillian (I'd Give My Heart), Our Solemn Hour, The Cross, Sinéad and Forgiven. He uses Roland keyboards on stage.

Spierenburg also wrote orchestral arrangements for the band, and oversaw the orchestra when the band was recording albums.

In December of 2024 he announced his departure from Within Temptation.