Didactics
In recent years, 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.
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