Leadpipe or mouthpipe system for trombone or other brass instrument

A leadpipe for a musical instrument comprising: a sidewall defining an enclosed channel, the sidewall having an upstream end and a downstream end; wherein the sidewall is comprised of a plurality of sections including a first tapered section and at least one subsequent tapered section; wherein each of the sections extends longitudinally between the upstream end and the downstream end of the sidewall; wherein the first tapered section is disposed upstream of the at least one subsequent tapered sections; wherein the first tapered section and at least one subsequent tapered section of the sidewall each define a generally frustoconical cavity having an upstream inner diameter Df and a downstream inner diameter Ds; and wherein the downstream diameter of each of the tapered sections that defines a generally frustoconical cavity is larger than the upstream diameter. The leadpipe may produce greater intensity of overtones and improved sound quality.