These pages comprise a dictionary of terms relating to the pipe organ. Please keep definitions to a few sentences, and do not include pictures or sound clips. When more space is needed for a term, a new page can be created for it.
Radiating [adj.] a term used to describe a pedalboard whose pedals are not parallel, but whose inner ends are splayed slightly further apart from each other than the outer ends. Radiating pedalboards are often (but not always) also concave.
Rank [noun] a matched set of pipes of consistent timbre and volume, with one pipe for each note. One stop usually controls one rank, but may control more than one rank (see Compound Stop). Multiple stops may also control a single rank (see Borrowing, Duplexing and Unification).
Rauschwerk [noun] - a non-repeating quint mixture stop of two (or more) ranks, generally 2' + 1-1/3'. Also, in early usage, a refined chorus reed, or a compound Cornet-like stop which imitates a reed.
Récit [noun] - the third or fourth topmost manual in the French classic organ, of short compass and containing a cornet and perhaps a reed. Chest located above the Grande Orgue.
Récit Expressif [noun] - the third or fourth topmost manual in the French Romantic organ as typified in the instruments of Cavaillé-Coll. It was enclosed in a swell box, was usually of full compass, and had chorus reeds, commonly with an Hautbois, flutes, possibly harmonic, and usually a string celeste and Voix Humaine with tremulant. Larger instruments might have a principal chorus with mixture(s) and a cornet. This division was indepensible in the desired crescendo from pp to full organ.
Reed [noun] 1. a type of organ pipe in which the sound is produced by a vibrating metal reed or tongue. 2. the part of a reed pipe which vibrates and creates the sound; more properly known as the Tongue.
Regal - a family of reed stops which produce a variety of narrow or nasal tone, usually having shorter than average resonators, which produces the opposite effect of a "Harmonic Reed"
Relay[noun] - a device used to transfer control of electrical contacts. In an organ, a mechanico-electrical or electronic machine used to translate key presses and stop selections to individual pallets that release wind to pipes allowing them to sound. In some, percussive instruments are sounded rather than pipes.
Resonator [noun] - the tube part of a reed pipe which produces no sound on its own, but which resonates to amplify the note produced by the vibrating reed.
Resultant [noun] - a stop, usually on the Pedal Division, which sounds two pipes, a fifth apart, to produce the effect of a note an octave below the lower pipe. A way to simulate a 32' pitch from two pipes in the 16' octave.
Reversible [noun] - a thumb piston or toe stud on an organ console which produces a change when pressed once, and reverses that change if pressed again. Often used for couplers.
Rohrflöte [noun] a flue stop the pipes of which are surmounted by a tube, markedly smaller in diameter than the body of the pipe.
Rohrwerk [noun] reed stops.
Roller-Board [noun] - a mechanical device for accomodating changes of direction, spacing or order in the mechanical linkages of an organ. A tracker action organ would normally have several roller boards.
Rückpositiv [noun] - German term for the division behind the organist's back, usually designed as a foil to the Hauptwerk. In addition to a small chorus, it commonly contained solo reed(s) and partial-pitch stops (2-2/3', 1-3/5', 1-1/7' etc.) for color.
Rugwerk [noun] - the Dutch term for "Rückpositiv".