Jacks were a 1960s Japanese psychedelic rock group who released their best known studio album Vacant World in 1968. The Jacks, originally known as "Nightingale", began their career in 1966 as a folk trio. After jazz drummer Takasuke Kida joined the group they headed into a new musical direction. Vacant World, released in 1968 as Karappo No Sekai (Vacant World) or Jacks no Sekai (Jacks' World) in Japanese, is widely seen as one of the most important Japanese albums. Read more on Last.fm