Barker lever
The Barker lever (also known as the Barker machine ) is a pneumatic relay that is used in organ building to reduce the forces required to operate a tone valve.
In general , the larger the organ , the greater the forces acting on a mechanical action and thus on the key . In order to still be able to play large organs, various devices have been developed which reduce the pressure exerted by the player on the key. The English organ builder Charles Spackman Barker (1804–1879) had been developing his "pneumatic machine" since 1832 , later called the Barker lever , which was initially used in the organs of Cavaillé-Coll .
The push of a button does not directly open the pipe valve, but a valve in an additional wind chest , the so-called play wind chest . This inflates a small working bellows, which then pulls the actual sound tract. The advantage of a lower pressure point comes at the price of the fact that the sound responds with a certain delay. Also, in contrast to other game aids such. B. the pilot valve , the direct connection between button and valve is lost.
literature
- Hans-Dieter Meyer: Buchholz and Haupt, or: How the Barker lever came to Germany. In: Ars Organi . Vol. 52, 2004. ISSN 0004-2919
- John William Hinton: The Story of the Electric Organ . Simpkin, Marshall, Hamilton, Kent & Co., London 1909, OCLC 560608898 .
- Nicholas Thistlethwaite: The Making of the Victorian Organ. (= Cambridge Musical Texts and Monographs ). Cambridge University Press, 1990, ISBN 0-521-34345-3 , pp. 352-354.
- P. Williams: Organ. In: Stanley Sadie (Ed.): The New Grove Dictionary of Music & Musicians. Vol. 13, Macmillan, New York 1995, ISBN 1-56159-174-2 , pp. 710-779.