The pipe organ began as a water-powered machine in ancient Alexandria
Mozart called it the king of instruments, and before the Industrial Revolution the pipe organ ranked with the clock among humanity's most complex machines. Its ancestor was the hydraulis, a water-powered organ invented by Ctesibius of Alexandria in the 3rd century BC and played at Greek and Roman games.
An organ is a keyboard instrument that sounds tones through pipes or through reeds or electronics imitating them. Players use two or three keyboards for the hands, sometimes five or more, plus a pedalboard for the feet, and stops let many ranks of pipes be coupled to a single keyboard. Unlike a piano key, an organ key is simply on or off, so volume is shaped by shutters on an enclosed swell box. Its ancestry runs back to panpipes, and the double-piped Greek aulos gave the hydraulis its name.
From the Greek and Roman world the instrument passed to Byzantium, where it served court and secular music. In 757 the Byzantine emperor Constantine V sent one as a gift to Pippin in the West, and there it gradually became central to Catholic worship; tradition credits Pope Vitalian with bringing organs into churches in the 7th century. In the 9th century the Banū Mūsā brothers built an automatic flute player that may have been a water-driven organ. The instrument's current form dates from the 14th century.
Size is where the organ astonishes. It is the largest musical instrument, ranging from about a cubic metre to five storeys tall, with some examples carrying over 10,000 pipes. The biggest pipes are 64 feet long and sound a fundamental of 8 hertz, below what most people hear as a note. The Wanamaker Organ in Philadelphia can match the sonic resources of three symphony orchestras playing at once, and any organ can sustain a chord for as long as the player holds it.
The family has many branches. Reed organs and harmoniums excite free reeds as an accordion or harmonica does; the Hammond is an electromechanical organ played through loudspeakers; barrel organs play from pinned cylinders cranked by an organ grinder. In church the pipe organ earns its place because it can underpin, support and brighten human voices at once.
Source: Organ (music)
