He listened to Kjell Öhman 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).

That gave him the opportunity to play with Ove Johansson, Jan Forslund, Conny Sjökvist, Gilbert Holmström, Gunnar Lindgren, and others, and he discovered Herbie Hancock, McCoy Tyner, Paul Bley, Bill Evans, Lennie Tristano, Keith Jarrett, and Chick Corea.

He went on to play with Radka Toneff and various Norwegian musicians, including Knut Riisnaes and Jan Garbarek, and then with Hawk on Flight, Equinox, Red Mitchell, Joakim Milder, Crystal Eagle, and many other groups, both Swedish and Danish.

Lars Jansson Trios member are now Thomas Fonnesbaek-bass (Copenhagen) and his son Paul Svanberg (Stockholm) on drums.