For ages the Indian bansuri has been a mere folk instrument, associated with the popular god Krishna. It has entered the classical stage only in the 20th century. An influential pioneer in the 1950s and 60s was Pannalal Ghosh, who adopted the dominating vocal khyal style for the bansuri. From the 1970s onwards the creative genius of Hariprasad Chaurasia has further enriched the repertory by elements of dhrupad alap and techniques of plucked instruments. Solo performers usually use pretty large instruments with a tonic Sa between low F and D. These bansuris are difficult to hold because of their length, but they produce a wonderfully deep and warm sound.