C.G. Conn Step-Up Model 20KSP Brass Sousaphone

About the Model 20KSP

The "original" sousaphone. This large bore sousaphone has the most sought after sound for the marching field. Ergonomically friendly as well as improved bracing over time for the demands of todays marching activity.


Historic design in sousaphones, the C.G. Conn 20K originated from the concepts of John Philip Sousa in the early 1900's. This large bore .734" with a 26" bell sousaphone offers great ergonomics and durability. Improved bracing along with short action, offset pistons offers great versatility for any sousaphone section. Silver plated.

Tech Specs

  • Key of BBb
  • .734"/18.64mm bore
  • Yellow brass branch and bell
  • 26"/660.40mm bell diameter
  • 3, short stroke pistons
  • Silver plate finish
  • 18 mouthpiece