Device in a roll frame which keeps the music roll centered and aligned with the holes in the tracker bar by shifting the supply spool (most common), both spools, or the tracker bar. * Synonym: automatic tracking mechanism.

To shift music into a higher or lower key without making any other changes.

Device which enables the tracker bar, especially of a piano, to shift laterally for up to several notes so as to transpose the music arrangement to a higher or lower range for use in accompanying a singer. The sustaining pedal hole in many tracker bars is several perforations wide, or is located in a separate stationary part of the bar, permitting automatic sustain to work when the music is played in several different keys. Not used in instruments with other control perforations in the tracker bar, because transposing the tracker bar would confuse the controls (exception: some very late Duo-Art reproducing pianos in which only the note-playing portion of the tracker bar shifts).

Term denoting non-tuned percussion instruments and sound effects in a large orchestrion or dance organ. * Synonym: traps. * German: Schlagwerk

The upper range of the musical scale (as opposed to bass). * German: diskant.