Lars Jansson was born in 1951, and grew up in Orebro, Sweden, where he was bored by his lessons at the community music school. In his early teens, a relative lent him records with Miles Davis, Ben Webster, and Mose Allsion. During the 1960s, he followed the fashion and developed an interest in the organ. He listened to Kjell Ohman play with the Telstars, to Jimmy Smith and Jack McDuff, and to Hammond organ music. Drummer Sjunne Ferger became an important figure in his life, and together they formed a duo: "Takt & Ton" (Beat & Pitch).
In 1970, after graduation from upper secondary school, he took a semester off, planning to go on and study medicine