Kellner's major contribution to the musical corpus was "Truelicher Unterricht im General-Bass" published in 1732. The treatise was quite popular and went into editions as late as 1796 having been translated into Swedish and Dutch. His explanations were succinct and less than one hundred pages. He discussed important thoroughbass compositions by Mattheson and Heinichen using them to cover diverse subjects including chord structures, intervals, the use of figures, accompaniment, unusual progressions, and consonance and dissonance. In Sweden, Kellner was an organist in Stockholm for The Jacobi Jyrka and the carillonneur for the German church. He was one of the most accomplished lutenists in Germany and among the last virtuoso performers on that instrument. "Auserlesene Lauten-Stucke" was a collection of seventeen lute pieces in numerous forms including dances, fantasies and variations. ~ Keith Johnson, Rovi