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.
Pedal [noun] - the division of the organ with the lowest-sounding ranks, and played by the organist's feet. The pedal division is usually designed around the 16' pitch level, and in large instruments around the 32' level.
Pedalboard [noun] a set of keys that are played with the feet.
Pipe [noun] - short for "organ pipe".
Pipe Maker [noun] - a person or firm who makes organ pipes.
Piston [noun] - a small cylindrical button located (typically in groups) between the manuals of an organ console. These usually operate the Combination Action. See also "Toe Stud".
Pitman Chest - A type of electropneumatic action highly developed particularly in American organs in the 20th century.
Plein Jeu [noun] - a mixture, occasionally of somewhat lower pitch than others, and frequently having a large number of ranks (V or VI or more). Rarely has third-sounding ranks, but often contains sub-unison partials. In the French Classic school, a specific combination of stops (principals, flutes, low and high mixtures), or a piece written to be played on that combination.
Pneumatic[adjective] - having to do with wind pressure, operated by wind pressure. When describing an organ's key action, short for "Tubular Pneumatic"
Pneumatic[noun] - Short for "pneumatic motor". A device, usually wedge-shaped, which is inflated by wind pressure and moves some other hardware, switch, etc.
Polyphonic Pipe [noun] a single organ pipe which is capable of producing more than one note, though only one note at a time. Used rarely, and only for the largest and most expensive pedal pipes.
Portative - A small organ used in 12th-16th century Europe. It had few keys (perhaps two octaves) of a single flue stop, designed in a cabinet to be carried as it is played, usually in secular music. The performer would work the bellows with one hand and play the keyboard with the other.
Positiv - A secondary division of the organ, designed as a tonal foil to the Great division. It would be smaller in scope, with a higher pitch base. In the North German ideal, it was usually mounted on the rail behind the organist's back and was called the Ruckpositiv. The French version was the Positif; the English equivalent was the Chair organ.
Praetorius, Michael (1571? - 1621) German organist, composer, scholar and music theorist. Composed vocal and instrumental church music, famous dance collection Terpsichore. Wrote a three-volume treatise on music, Syntagma Musicum, including a famous description of the organ as it was built and played in his time in volume 2.
Pull-Down [noun] The linkage (usually a wire trace) which connects a pallet to its actuating mechanism. In mechanical action instruments, the pull-down would normally pass through the base of the windchest and attach to the end of a tracker. In pneumatic/electro-pneumatic/direct electric actions, the pull-down may connect to a pneumatic motor or solenoid within the windchest.