Sackbut as ballet "Don Juan" (1761). Some chamber music in this period includes trombone in an obligato role with voice, and also as a concerto instrument with string orchestra. Composers include the likes of Leopold Mozart, Georg Christoph Wagenseil, Johann Albrechtsberger, Michael Haydn and Johann Ernst Eberlin. For works for trombone post-1800, please see trombone. Many groups specializing in period music make frequent and prominent use of the sackbut. External links: Plenty of recordings of the authentic sackbut are now available from the groups such as Concerto Palatino, HMSC, Gabrieli Consort and the Toulouse Sacqueboutiers. For a closer examination of the
Recorder (musical instrument) In recorders, like in all woodwind instruments, the air column inside the instrument behaves like a vibrating string, to use a musical analogy, and has multiple modes of vibration. These waves produced inside the instrument are not longitudinal waves, like those the ear perceives as sound, but rather stationary standing waves consisting of areas of high pressure and low pressure inside the tube, called nodes. The perceived pitch is the lowest, and typically loudest, mode of vibration in the air column. The other pitches are "harmonics", or "overtones". Players typically describe recorder pitches by the number of nodes in the