Aeolian harp

An aeolian harp (or æolian harp or wind harp) is a musical instrument that is "played" by the wind. It is named for Aeolus, the ancient Greek god of the wind.

History

Aeolian harps were very popular as household instruments during the Romantic Era, and are still hand-crafted today. Some are now made in the form of monumental metal sound sculptures located on the roof of a building or a windy hilltop.

Description

The traditional aeolian harp is essentially a wooden box including a sounding board, with strings stretched lengthwise across two bridges. It is placed in a slightly opened window where the wind can blow across the strings to produce sounds. The strings can be made of different materials (or thicknesses) and all be tuned to the same note, or identical strings can be tuned to different notes.

Sound

The sound is random, depending on the strength of the wind passing over the strings, and can range from a barely audible hum to a loud scream. If the strings are tuned to different notes, sometimes only one tone is heard and sometimes chords.

Operation

The harp is driven by von Karman vortex street effect. The motion of the wind across a string causes perioding vortex downstream and this alternating vortex cause the string tovibrate. Lord Rayleigh first solved the mystery of aeolin harp in a paper published in the Philosophy Magazine. [Lord Rayleigh, Aeolian Tones, Philosophical Magazine series 6 1915] The effect can sometimes be observed in overhead utility lines, fast enough to be heard or slow enough to be seen. A stiff rod will perform; a non-telescoping automobile radio antenna can be a dramatic exhibitor. And of course the effect can happen in other media; in the anchor line of a ship in a river, for example.

Aeolian harps in literature and music

Aeolian harps are featured in at least two Romantic-era poems, "The Aeolian Harp" and "Dejection, an Ode", both by Samuel Taylor Coleridge. In William Heinesen's novel "The Lost Musicians" set in Tórshavn, Kornelius Isaksen takes his three sons to a little church where, in the tower, they sit listening to the 'capriciously varying sounds of an Aeolian harp', which leads the boys into a lifelong passion for music.Aeolian harps are mentioned in Vladimir Nabokov's classic Lolita.
Henry Cowell's "Aeolian Harp" (1923) was one of the first piano pieces ever to feature extended techniques on the piano which included plucking and sweeping the pianist's hands directly across the strings of the piano. The Etude in A flat major for piano (1836) by Frédéric Chopin (Étude Op. 25, No. 1 (Chopin)) is sometimes called the "Aeolian Harp" etude, a nickname given it by Robert Schumann. The piece features a delicate, tender, and flowing melody in the fifth finger of the pianist's right hand, over a background of rapid pedaled arpeggios. One of Sergei Lyapunov's "12 études d'exécution transcendante", Op.11 No.9, is named by the author "Harpes éoliennes" (aeolian harps). In this virtuoso piece, written between 1897 and 1905, the tremolo accompaniment seems to imitate the sounding of the instrument.

In 1972, Chuck Hancock and Harry Bee recorded a giant 30 foot tall Aeolian harp designed and built by 22 year-old Thomas Ward McCain on a hilltop in Chelsea, Vermont. United released their double LP entitled The Wind Harp - Song From The Hill. (An excerpt of this recording appears in the movie The Exorcist.) In the spirit of this, in 2003 an Aeolian harp was constructed at Burning Man. Australian artist, composer and sound sculptor Alan Lamb has created and recorded several very large scale aeolian harps.

Builders of pipe organs have included stops intended to imitate the sound and timbre of the aeolian harp. German builders were the first to include such a stop from the 1820s. The Aeolian Harp stop is not a harp- it is simply a rank of pipes using a low wind pressure and voiced to imitate the sound of the real instrument. It is therefore classified as a 'string' stop. These stops are amongst the softest found on pipe organs

References