sound of a trombone with a harmon mute is featured as the voices of adults in the Peanuts cartoons. Didactics Several makers have begun to market compact B♭/C trombones that are especially well suited for young children learning to play the trombone who cannot reach the outer slide positions of full-length instruments. The fundamental note of the unenhanced length is C, but the short valved attachment that puts the instrument in B♭ is open when the trigger is not depressed. While such instruments have no seventh slide position, C and B natural may be comfortably accessed on the first and second positions by using the trigger. A similar design ("Preacher model") was marketed by C.G. Conn in the 1920s, also under the Wurlitzer label. Currently, B♭/C trombones are available from many manufacturers, including German makers Günter Frost, Thein and Helmut Voigt, as well as the Yamaha Corporation. Manufacturers Trombones in slide and valve configuration have been made by a vast array of musical instrument manufacturers. For the brass bands of the late 19th and early 20th century, prominent American manufacturers included Graves and Sons, E. G. Wright and Company, Boston Musical Instrument Company, E. A. Couturier, H. N. White Company/King Musical Instruments, J. W. York, and C.G. Conn. In the 21st century, leading mainstream manufacturers of trombones include Bach, Conn, Courtois, Edwards, Getzen, Jupiter, King, Rath, Schilke, S.E. Shires, Thein, Willson and Yamaha. See also Aequale Shout band Trombone repertoire References Further reading Carter, Stewart (2011). The Trombone in the Renaissance: A History in Pictures and Documents. Bucina: The Historic Brass Society Series. Hillsdale, N.Y.: Pendragon Press. . External links International Trombone Association Online Trombone Journal British Trombone Society Trombone History Timeline by Will Kimball, Professor of Trombone at Brigham Young University Acoustics of Brass Instruments from Music Acoustics at the University of New South Wales Sources for the Prescribed Sheet Music for the ABRSM practical exams Two Frequencies Trombone NPR story about trombone bands (2003) Overview of trombones on the MIMO (Musical Instrument Museums Online) portal Slide positions Christian E. Waage (2009). "Slide Position Chart", YeoDoug.com Antonio J. García. (1997). "Choosing Alternate Positions for Bebop Lines", GarciaMusic.com. B-flat instruments Bass (sound) Continuous pitch instruments Jazz instruments Marching band instruments Orchestral instruments