Mark Alan Knight (born 8 January 1973), also known as TDK and Madfiddler, is a British musician, video game music composer and sound designer. He started out writing chiptune and module file music in the Amiga demoscene, and began his games industry career as a composer in 1992. He continued until 2000 when he moved to sound design, and since 2014 has had a split role as a sound designer and composer.