Pipe organ

The pipe organ is a musical instrument that produces sound by driving pressurized air (called wind) through pipes selected via a keyboard. Because each organ pipe produces a single pitch, the pipes are provided in sets called ranks, each of which has a common timbre and volume throughout the keyboard compass. Most organs have multiple ranks of pipes of differing timbre, pitch and volume that the player can employ singly or in combination through the use of controls called stops.

A pipe organ has one or more keyboards played by the hands (called manuals), and a pedalboard played by the feet; each keyboard has its own group of stops. The keyboard(s), pedalboard, and stops are housed in the organ's console. The organ's continuous supply of wind allows it to sustain notes for as long as the corresponding keys are depressed, unlike the piano and harpsichord whose sound begins to decay immediately after attack. The smallest portable pipe organs may have only one or two dozen pipes and one manual; the largest may have over 20,000 pipes and seven manuals. A list of some of the most notable and largest pipe organs in the world can be viewed at List of pipe organs.