Editing Pipe organ (section)

===Pipes===
{{Main|Organ pipe}}
[[File:Salt Lake City Organ.jpg|thumb|The [[Salt Lake Tabernacle organ]] found at the [[Salt Lake Tabernacle]] in [[Salt Lake City]], Utah, has 11,623 pipes and accompanies [[The Tabernacle Choir at Temple Square]] and [[Orchestra at Temple Square]].]]
Organ pipes are made from either wood or metal and produce sound ("speak") when air under pressure ("wind") is directed through them.<ref>Randel "Organ", 578.</ref> As one pipe produces a single [[pitch (music)|pitch]], multiple pipes are necessary to accommodate the [[musical scale]]. The greater the length of the pipe, the lower its resulting pitch will be.<ref name="randel579">Randel "Organ", 579.</ref> The [[timbre]] and volume of the sound produced by a pipe depends on the volume of air delivered to the pipe and the manner in which it is constructed and voiced, the latter adjusted by the [[Organ building|builder]] to produce the desired tone and volume. Hence a pipe's volume cannot be readily changed while playing.<ref name="randel579" />

[[File:Spain Andalusia Seville BW 2015-10-23 12-30-25 stitch.jpg|thumb|right|Interior of the [[Seville Cathedral]], showing the pipes of the organ.]]
Organ pipes are divided into [[flue pipe]]s and [[reed pipe]]s according to their design and timbre. Flue pipes produce sound by forcing air through a [[fipple]], like that of a [[recorder (musical instrument)|recorder]], whereas reed pipes produce sound via a beating [[Reed (instrument)|reed]], like that of a clarinet or saxophone.<ref>Bicknell "Organ construction", 27.</ref>

Pipes are arranged by timbre and pitch into ranks. A rank is a set of pipes of the same timbre but multiple pitches (one for each note on the keyboard), which is mounted (usually vertically) onto a [[#Wind system|windchest]].<ref name="Bicknell 20">Bicknell "Organ construction", 20.</ref> The [[organ stop#Mechanics|stop mechanism]] admits air to each rank. For a given pipe to sound, the stop governing the pipe's rank must be engaged, and the key corresponding to its pitch must be depressed. Ranks of pipes are organized into groups called divisions. Each division generally is played from its own keyboard and conceptually comprises an individual instrument within the organ.<ref>Gleason, 3–4.</ref>