Swedish percussionist, multi-instrumentalist and music producer, born July 16, 1957 in Örgryte parish. His artist name is Per Cussion.

Tjernberg was a member of Dag Vag in 1982–83 and has also been a member of Archimedes Badkar, Pep's Blodsband and Aston Reymers Rivaler. He has since released nine albums in his own name, including Don’t Stop (1983), which is considered to be the first Swedish rap album. Plays since 2010 with Wasa Express.