Which sounds with the help of pipes (metal, wooden, without reeds and with reeds) of various timbres, into which air is blown with the help of bellows.
Organ playing is carried out using several keyboards for hands (manuals) and a pedal keyboard.
In terms of sound richness and abundance of musical means, the organ ranks first among all instruments and is sometimes called the “king of instruments”. Due to its expressiveness, it has long been the property of the church.
A person who plays music on an organ is called organist.
Soldiers of the Third Reich called the Soviet multiple launch rocket systems BM-13 "Stalin's organ" because of the sound made by the plumage of the missiles.
History of the organ
The embryo of the organ can be seen in, as well as in. It is believed that the organ (hydraulos; also hydraulikon, hydraulis - “water organ”) was invented by the Greek Ktesibius, who lived in Alexandria of Egypt in 296-228. BC e. Image similar instrument is available on one coin or token from the time of Nero.
Organs large sizes appeared in the 4th century, more or less improved organs - in the 7th and 8th centuries. Pope Vitalian (666) introduced the organ into the Catholic Church. In the 8th century, Byzantium was famous for its organs.
The art of building organs also developed in Italy, from where they were sent to France in the 9th century. Later this art developed in Germany. The organ began to receive the greatest and widespread distribution in the XIV century. In the 14th century, a pedal appeared in the organ, that is, a keyboard for the feet.
Medieval organs, in comparison with later ones, were of crude workmanship; a manual keyboard, for example, consisted of keys with a width of 5 to 7 cm, the distance between the keys reached one and a half cm. They hit the keys not with fingers, as they do now, but with fists.
In the 15th century, the keys were reduced and the number of pipes increased.
Organ device
Improved organs reached a huge number of pipes and tubes; for example, the organ in Paris in the church of St. Sulpice has 7 thousand pipes and tubes. In the organ there are pipes and tubes of the following sizes: at 1 foot, notes sound three octaves higher than written, at 2 feet, notes sound two octaves higher than written, at 4 feet, notes sound an octave higher than written, at 8 feet, notes sound as they are written, at 16 feet - notes sound an octave below written, at 32 feet - notes sound two octaves below written. Closing the pipe from above leads to a decrease in the emitted sounds by an octave. Not all organs have large tubes.
There are from 1 to 7 keyboards in the organ (usually 2-4); they are called manuals. Although each organ keyboard has a volume of 4-5 octaves, thanks to the pipes sounding two octaves below or three octaves above the written notes, the volume of a large organ has 9.5 octaves. Each set of pipes of the same timbre is, as it were, a separate instrument and is called register.
Each of the retractable or retractable buttons or registers (located above the keyboard or on the sides of the instrument) actuates a corresponding row of tubes. Each button or register has its own name and a corresponding inscription, indicating the length of the largest pipe of this register. The composer can indicate the name of the register and the size of the pipes in the notes above the place where this register should be applied. (The choice of registers for the performance of a piece of music is called registering.) Registers in the organs are from 2 to 300 (most often found from 8 to 60).
All registers fall into two categories:
- Registers with pipes without reeds(labial registers). This category includes registers of open flutes, registers of closed flutes (bourdons), registers of overtones (potions), in which each note has several (weaker) harmonic overtones.
- Registers with pipes with reeds(reed registers). The combination of registers of both categories together with a potion is called plein jeu.
The keyboards or manuals are located in the terraced organs, one above the other. In addition to them, there is also a pedal keyboard (from 5 to 32 keys), mainly for low sounds. The part for the hands is written on two staves - in the keys and as for. The pedal part is often written separately on the same staff. The pedal keyboard, simply called the "pedal", is played with both feet, using the heel and toe alternately (until the 19th century, only the toe). An organ without a pedal is called positive, a small portable organ is called portable.
Manuals in organs have names that depend on the location of the pipes in the organ.
- The main manual (having the loudest registers) - in the German tradition is called Hauptwerk(French Grand orgue, Grand clavier) and is located closest to the performer, or on the second row;
- The second most important and loud manual in the German tradition is called Oberwerk(louder version) or Positive(light version) (fr. Рositif), if the pipes of this manual are located ABOVE the pipes of Hauptwerk, or Ruckpositiv, if the pipes of this manual are located separately from the rest of the pipes of the organ and are installed behind the back of the organist; the Oberwerk and Positiv keys on the game console are located one level above the Hauptwerk keys, and the Ruckpositiv keys are one level below the Hauptwerk keys, thereby reproducing architectural structure tool.
- The manual, the pipes of which are located inside a kind of box, which has vertical shutters in the front part of the blinds in the German tradition are called Schwellwerk(fr. Recit (expressif). Schwellwerk can be located both at the very top of the organ (more common), and on the same level as the Hauptwerk. The Schwellwerka keys are located on the game console at a more high level than Hauptwerk, Oberwerk, Positiv, Ruckpositiv.
- Existing types of manuals: Hinterwerk(pipes are located at the back of the organ), Brustwerk(pipes are located directly above the organist's seat), Solowerk(solo registers, very loud trumpets located separate group), Choir etc.
The following devices serve as relief for the players and a means for amplifying or attenuating sonority:
copula- a mechanism by which two keyboards are connected, with the registers advanced on them acting simultaneously. The copula enables the player on one manual to use the extended registers of another.
4 footrests above pedal board(Pеdale de combinaison, Tritte), each of which acts on a certain combination of registers.
Blinds- a device consisting of doors that close and open the entire room with pipes of different registers, as a result of which the sound is strengthened or weakened. Doors are set in motion by a footboard (channel).
Since registers in different bodies different countries and epochs are not the same, then in the organ part they are usually not indicated in detail: they write out only the manual, the designation of pipes with or without reeds, and the size of the pipes above this or that place in the organ part. The rest of the details are provided to the performer.
The organ is often combined with the orchestra and singing in oratorios, cantatas, psalms, and also in opera.
There are also electric (electronic) organs, for example, Hammond.
Composers who composed organ music
Johann Sebastian Bach
Johann Adam Reinken
Johann Pachelbel
Dietrich Buxtehude
Girolamo Frescobaldi
Johann Jakob Froberger
Georg Friedrich Handel
Siegfried Karg-Elert
Henry Purcell
Max Reger
Vincent Lübeck
Johann Ludwig Krebs
Matthias Weckman
Domenico Zipoli
Cesar Frank
Video: Organ on video + sound
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Subtitles
Terminology
Indeed, even in inanimate objects there is this kind of ability (δύναμις), for example, in [musical] instruments (ἐν τοῖς ὀργάνοις); they say about one lyre that it is capable [of sounding], and about the other - that it is not, if it is dissonant (μὴ εὔφωνος).
That kind of people who deal in instruments spends all their labor on it, like, for example, a kifared, or one who demonstrates his craft on the organ and other musical instruments (organo ceterisque musicae instrumentis).
Fundamentals of Music, I.34
In Russian, the word "organ" by default means wind organ, but is also used in relation to other varieties, including electronic analog and digital, which imitate the sound of an organ. Organs are:
- by device - wind, reed, electronic, analog, digital;
- by functional affiliation - concert, church, theatrical, fair, salon, educational, etc .;
- by disposition - baroque, French classical, romantic, symphonic, neo-baroque, modern;
- by the number of manuals - one-manual, two-, three-, etc.
The word "organ" is also usually qualified by reference to the organ builder (e.g. "Cavaillé-Cohl Organ") or trademark("Organ Hammond"). Some varieties of the organ have independent terms: antique hydraulics, portable, positive, regal, harmonium, hurdy-gurdy, etc.
Story
The organ is one of the oldest musical instruments. Its history goes back several thousand years. Hugo Riemann believed that the ancient Babylonian bagpipe (19th century BC) was the ancestor of the organ: “The fur was inflated through a pipe, and at the opposite end there was a body with pipes, which, no doubt, had tongues and several holes.” The germ of the organ can also be seen in the pan flute, the Chinese sheng, and other similar instruments. It is believed that the organ (water organ, hydraulics) was invented by the Greek Ctesibius, who lived in Alexandria Egyptian in 296-228. BC e. The image of a similar tool is available on one coin or token from the time of Nero. Large organs appeared in the 4th century, more or less improved organs in the 7th and 8th centuries. Pope Vitalian is traditionally credited with introducing the organ into Catholic worship. In the 8th century, Byzantium was famous for its organs. The Byzantine emperor Constantine V Kopronym in 757 presented the organ to the Frankish king Pepin the Short. Later, the Byzantine Empress Irina presented his son, Charles the Great, with an organ that sounded at the coronation of Charles. The organ was considered at that time a ceremonial attribute of the Byzantine, and then the Western European imperial power.
The art of building organs also developed in Italy, from where they were sent to France in the 9th century. This art later developed in Germany. ubiquitous distribution in Western Europe the organ has been received since the 14th century. Medieval organs, in comparison with later ones, were of crude workmanship; a manual keyboard, for example, consisted of keys with a width of 5 to 7 cm, the distance between the keys reached one and a half cm. They hit the keys not with fingers, as they do now, but with fists. In the 15th century, the keys were reduced and the number of pipes increased.
The oldest example of a medieval organ with relatively complete mechanics (pipes have not been preserved) is considered to be an organ from Norrlanda (a church parish on the island of Gotland in Sweden). This tool is usually dated to 1370-1400, although some researchers doubt such an early dating. The Norrland organ is currently kept at the National historical museum in Stockholm.
In the 19th century, thanks primarily to the work of the French organ master Aristide Cavaille-Coll, who set out to design organs in such a way that they could compete with the sound of a whole symphony orchestra with their powerful and rich sound, instruments of a previously unprecedented scale and power of sound began to appear. , which are sometimes called symphonic organs.
Device
Remote controller
Remote organ ("spiltish" from German Spieltisch or organ department) - a remote control with all the tools necessary for an organist, the set of which is individual in each organ, but most have common ones: gaming - manuals And pedal keyboard(or simply "pedal") and timbre - switches registers. There may also be dynamic channels, various foot levers or buttons to turn on copula and switching combinations from register combination memory bank and a device for turning on the organ. At the console, on a bench, the organist sits during the performance.
- Copula - a mechanism by which the included registers of one manual can sound when played on another manual or pedal. The organs always have copulas of manuals for the pedal and copulas for the main manual, and there are almost always copulas of weaker-sounding manuals for stronger ones. The copula is turned on/off by a special foot switch with a latch or a button.
- Channel - a device with which you can adjust the volume of this manual by opening or closing the blinds in the box in which the pipes of this manual are located.
- The register combination memory bank is a device in the form of buttons, available only in organs with an electric register tracture, which allows you to memorize register combinations, thereby simplifying register switching (changing the overall timbre) during performance.
- Ready-made register combinations - a device in organs with a pneumatic register tracture that allows you to turn on a ready-made set of registers (usually p, mp, mf, f)
- (from Italian Tutti - all) - the button for turning on all the registers and copulas of the organ.
Manuals
The first musical instruments with an organ pedal date back to the middle of the 15th century. - this is tablature German musician Adama of Ileborg (English) Russian(Adam Ileborgh, c. 1448) and the Buxheim Organ Book (c. 1470). Arnolt Schlick in Spiegel der Orgelmacher (1511) already writes in detail about the pedal and appends his pieces, where it is used with great virtuosity. Among them, the unique treatment of the antiphon stands out. Ascendo ad Patrem meum for 10 voices, of which 4 are entrusted to pedals. The performance of this piece probably required some kind of special shoes, which allowed one foot to simultaneously press two keys at a distance of a third. In Italy, notes using the organ pedal appear much later - in the toccatas of Annibale Padovano (1604).
Registers
Each row of pipes of a wind organ of the same timbre constitutes, as it were, a separate instrument and is called register. Each of the extendable or retractable drawbar knobs (or electronic switches) located on the organ console above the keyboards or on the sides of the music stand turns the corresponding row of organ pipes on or off. If drawbars are off, the organ will not sound when a key is pressed.
Each handle corresponds to the register and has its own name indicating the pitch of the largest pipe of this register - feet, traditionally denoted in feet in Principal. For example, the pipes of the Gedackt register are closed and sound an octave lower, so such a pipe of tone "to" subcontroctave is designated as 32", with an actual length of 16". Reed registers, whose pitch depends on the mass of the reed itself rather than on the height of the bell, are also indicated in feet, similar in length to the Principal register pipe in pitch.
The registers are grouped into families according to a number of unifying features - principals, flutes, gambas, aliquots, potions, etc. The main registers include all 32-, 16-, 8-, 4-, 2-, 1-foot registers, auxiliary (or overtone ) - aliquots and potions. Each pipe of the main register reproduces only one sound of the same pitch, strength and timbre. Aliquots reproduce an ordinal overtone to the main sound, mixtures give a chord, which consists of several (usually from 2 to a dozen, sometimes up to fifty) overtones to a given sound.
All registers for the device of pipes are divided into two groups:
- Labial- registers with open or closed pipes without reeds. This group includes: flutes (wide-scale registers), principals and narrow-scale ones (German Streicher - “streichers” or strings), as well as overtone registers - aliquots and potions, in which each note has one or more (weaker) overtone overtones.
- Reed- registers, in the pipes of which there is a tongue, when exposed to the supplied air, which produces a characteristic sound similar in timbre, depending on the name and design features of the register, with some wind orchestral musical instruments: oboe, clarinet, bassoon, trumpet, trombone, etc. Reed registers can be located not only vertically, but also horizontally - such registers make up a group that is from fr. chamade is called "shamad".
Connection of various types of registers:
- ital. Organo pleno - labial and reed registers along with potion;
- fr. Grand jeu - labial and reed without potions;
- fr. Plein jeu - labial with potion.
The composer can indicate the name of the register and the size of the pipes in the notes above the place where this register should be applied. The choice of registers for the performance of a musical work is called registration, and the included registers - register combination.
Since the registers in different organs of different countries and eras are not the same, they are usually not indicated in detail in the organ part: only the manual, the designation of pipes with or without reeds and the size of the pipes are written over one or another place in the organ part, and the rest is left to the discretion performer. Most of the musical organ repertoire does not have any author's designations regarding the registration of the work, so the composers and organists of previous eras had their own traditions and the art of combining different organ timbres was passed on orally from generation to generation.
Pipes
The register pipes sound different:
- 8-foot pipes sound in accordance with musical notation;
- 4- and 2-foot sounds one and two octaves higher, respectively;
- 16- and 32-footers sound one and two octaves lower, respectively;
- The 64-foot labial pipes found in the largest organs in the world sound three octaves below the record, therefore, those actuated by the keys of the pedal and manual below the counter-octave already emit infrasound;
- the labial tubes closed at the top sound an octave lower than the open ones.
A stimhorn is used to tune the organ's small open labial metal pipes. With this hammer-shaped tool, the open end of the pipe is rolled or flared. Larger open pipes are tuned by cutting a vertical piece of metal near or directly from the open end of the pipe, which is bent at one angle or another. Open wood pipes usually have a wood or metal adjuster that can be adjusted to allow the pipe to be tuned. Closed wood or metal pipes are adjusted by adjusting the plug or cap at the top end of the pipe.
Facade pipes of the organ can also play a decorative role. If the pipes do not sound, then they are called "decorative" or "blind" (eng. dummy pipes).
Traktura
An organ tractura is a system of transmission devices that functionally connects the controls on the organ's console with the organ's air-locking devices. The game tractor transmits the movement of the manual keys and the pedal to the valves of a particular pipe or group of pipes in a potion. The register tracture provides switching on or off of the whole register or a group of registers in response to pressing the toggle switch or moving the register handle.
Through the register tracture, the memory of the organ also acts - combinations of registers, pre-configured and embedded in the device of the organ - ready-made, fixed combinations. They can be named both by the combination of registers - Pleno, Plein Jeu, Gran Jeu, Tutti, and by the strength of sound - Piano, Mezzopiano, Mezzoforte, Forte. In addition to ready-made combinations, there are free combinations that allow the organist to select, memorize and change a set of registers in the organ's memory at his discretion. The function of memory is not available in all organs. It is absent in organs with a mechanical register tracture.
Mechanical
The mechanical tractura is a reference, authentic and the most common at the moment, allowing you to perform the widest range of works of all eras; mechanical tracture does not give the phenomenon of "delay" of sound and allows you to thoroughly feel the position and behavior of the air valve, which makes it possible for the best control of the instrument by the organist and the achievement of high performance technique. The key of the manual or pedal, when using a mechanical traction, is connected to the air valve by a system of light wooden or polymer rods (abstracts), rollers and levers; occasionally, in large old organs, a cable-block transmission was used. Since the movement of all these elements is carried out only by the effort of the organist, there are restrictions in the size and nature of the arrangement of the sounding elements of the organ. In giant organs (more than 100 registers), mechanical traction is either not used or supplemented by a Barker machine (a pneumatic amplifier that helps to press the keys; such are the French organs of the early 20th century, for example, the Great Hall of the Moscow Conservatory and the Church of Saint-Sulpice in Paris). The mechanical gaming is usually combined with the mechanical register tracture and windlad of the shleyflade system.
Pneumatic
Pneumatic tracture - the most common in romantic organs - from the end of the 19th century to the 20s of the 20th century; pressing the key opens a valve in the control air duct, the air supply to which opens the pneumatic valve of a particular pipe (when using windblade shleyflade, it is extremely rare) or a whole series of pipes of the same tone (windblade kegellade, characteristic of pneumatic traction). It allows building huge instruments in terms of the set of registers, as it has no power limitations of the mechanical tracture, however, it has the phenomenon of sound “delay”. This often makes it impossible to perform technically complex works, especially in “wet” church acoustics, given that the register delay time depends not only on the distance from the organ console, but also on its pipe size, the presence of relays in the tract, which accelerate the operation of the mechanics for due to the refreshment of the impulse, the design features of the pipe and the type of windlad used (almost always it is a kegellad, sometimes it is a membranenlad: it works to exhaust air, extremely fast response). In addition, the pneumatic tractor disconnects the keyboard with air valves, depriving the organist of the feeling of "feedback" and impairing control over the instrument. Pneumatic tracture of the organ is good for performing solo works of the Romantic period, difficult to play in an ensemble, and not always suitable for baroque and contemporary music.
Electrical
Electric tractor is a tractor widely used in the 20th century, with direct signal transmission from a key to an electromechanical valve opening-closing relay by means of a direct current pulse in an electrical circuit. Currently, more and more often replaced by mechanical. This is the only traktura that does not impose any restrictions on the number and location of the registers, as well as the placement of the organ console on the stage in the hall. It allows you to place groups of registers at different ends of the hall, control the organ from an unlimited number of additional consoles, play music for two and three organs on one organ, and also put the console in a convenient place in the orchestra, from which the conductor will be clearly visible. It allows you to connect several organs into a common system, and also provides a unique opportunity to record a performance with subsequent playback without the participation of an organist. The disadvantage of the electric tracture, as well as the pneumatic one, is the break in the "feedback" of the organist's fingers and air valves. In addition, an electric tractor can delay the sound due to the response time of the electric valve relays, as well as the distribution switch (in modern organs, this device is electronic and does not give a delay; in instruments of the first half and the middle of the 20th century, it was often electromechanical). When actuated, electromechanical relays often give additional "metallic" sounds - clicks and knocks, which, unlike similar "wooden" overtones of mechanical tracture, do not decorate the sound of the work at all. In some cases, the largest pipes of an otherwise completely mechanical organ (for example, in a new instrument from Hermann Eule in Belgorod) receive an electric valve, which is due to the need to preserve the area of the mechanical valve, and as a result, playing efforts, in the bass within acceptable limits. Noise can also be emitted by a register electric tractor when changing register combinations. An example of an acoustically excellent organ with a mechanical playing tracture and at the same time a rather noisy register tracture is the Swiss Kuhn organ in the Catholic Cathedral in Moscow.
Other
The largest organs in the world
The largest organ in Europe is the Great Organ of the Cathedral of St. Stephen in Passau (Germany), built by the German company Stenmayer & Co. It has 5 manuals, 229 registers, 17,774 pipes. It is considered the fourth largest operating body in the world.
Until recently, the largest organ in the world with a completely mechanical playing tracture (without the use of electronic and pneumatic control) was the organ of the Cathedral of St. Trinity in Liepaja (4 manuals, 131 registers, more than 7 thousand pipes), however, in 1979 in a large concert hall The Sydney Opera House Center for the Performing Arts installed an organ with 5 manuals, 125 registers and about 10,000 pipes. Now it is considered the largest (with a mechanical traction).
The main organ of the Cathedral in Kaliningrad (4 manuals, 90 registers, about 6.5 thousand pipes) is the largest organ in Russia.
Experimental Bodies
Organs of original design and tuning have been developed since the second half of the 16th century, such as, for example, the archiorgan of the Italian music theorist and composer N. Vicentino. However, such bodies have not received wide distribution. Today they are exhibited as historical artifacts in museums of musical instruments along with other experimental instruments of the past.
Organ- a unique musical instrument with a long history. One can speak about the organ only in superlatives: the largest in size, the most powerful in terms of sound strength, with the widest range of sound and a huge richness of timbres. That is why it is called the "king of musical instruments".
The progenitor of the modern organ is considered the Pan flute, which first appeared in Ancient Greece. There is a legend that the god of wildlife, pastoralism and cattle breeding Pan invented a new musical instrument for himself by connecting several reed pipes of different sizes in order to extract wonderful music while having fun with cheerful nymphs in luxurious valleys and groves. To successfully play such an instrument, great physical effort and a good respiratory system were required. Therefore, to facilitate the work of musicians in the 2nd century BC, the Greek Ctesibius invented a water organ or hydraulics, which is considered the prototype of the modern organ.
Organ development
The organ was constantly improved and in the 11th century it began to be built throughout Europe. The organ building reached its peak in XVII-XVIII centuries in Germany, where musical works for the organ were created, such great composers as Johann Sebastian Bach and Dietrich Buxtehude, unsurpassed masters of organ music.
The organs differed not only in beauty and variety of sound, but also in architecture and decor - each of the musical instruments had an individuality, was created for specific tasks, and harmoniously fit into the internal environment of the room. 
Only a room that has excellent acoustics is suitable for an organ. Unlike other musical instruments, the peculiarity of the sound of an organ does not depend on the body, but on the space in which it is located.
The sounds of the organ cannot leave anyone indifferent, they penetrate deep into the heart, evoke a wide variety of feelings, make you think about the frailty of life and direct your thoughts to God. Therefore, in Catholic churches and cathedrals, there were organs everywhere, the best composers wrote sacred music and played the organ with their own hands, for example, Johann Sebastian Bach.
In Russia, the organ belonged to secular instruments, since traditionally in Orthodox churches the sound of music during worship was prohibited.
Today's organ is a complex system. It is both a wind and keyboard musical instrument, having a pedal keyboard, several manual keyboards, hundreds of registers and from hundreds to more than thirty thousand pipes. Pipes are varied in length, diameter, type of structure and material of manufacture. They can be copper, lead, tin, or various alloys such as lead-tin. The complex structure allows the organ to have a huge range of sound in pitch and timbre and to have a wealth of sound effects. The organ can imitate the playing of other instruments, which is why it is often equated with a symphony orchestra. Most big organ located in the United States in the Boardwalk Concert Hall in Atlantic City. It has 7 hand keyboards, 33112 pipes and 455 registers.
The sound of the organ cannot be compared with any other musical instrument, and even symphony orchestra. Its powerful, solemn, unearthly sounds act on the soul of a person instantly, deeply and stunningly, it seems that the heart is about to burst from the divine beauty of music, the sky will open up and the secrets of life, incomprehensible until that moment, will open.
Source: « In the world of science » , No. 3, 1983. Authors: Neville H. Fletcher and Susanna Thwaites
The majestic sound of the organ is created due to the interaction of a strictly phase-synchronized air jet passing through a cut in the pipe and an air column resonating in its cavity.
No musical instrument can compare with the organ in terms of power, timbre, range, tonality and majesty of sound. Like many musical instruments, the structure of the organ has been constantly improved through the efforts of many generations of skilled craftsmen who slowly accumulated experience and knowledge. By the end of the XVII century. the body basically acquired its modern form. The two most prominent physics XIX V. Hermann von Helmholtz and Lord Rayleigh put forward opposing theories explaining the basic mechanism for the formation of sounds in organ pipes, but due to the lack of necessary instruments and instruments, their dispute was never resolved. With the advent of oscilloscopes and other modern instruments, it became possible to study in detail the mechanism of action of an organ. It turned out that both the Helmholtz theory and the Rayleigh theory are valid for certain pressures under which air is forced into the organ pipe. Further in the article, the results of recent studies will be presented, which in many respects do not coincide with the explanation of the mechanism of action of the organ given in textbooks.
Pipes carved from reeds or other hollow-stemmed plants were probably the first wind instruments. They make sounds if you blow across the open end of the tube, or blow into the tube, vibrating with your lips, or, pinching the end of the tube, blow in air, causing its walls to vibrate. The development of these three types of simple wind instruments led to the creation of the modern flute, trumpet and clarinet, from which the musician can produce sounds in a fairly large range of frequencies.
In parallel, such instruments were created in which each tube was intended to sound on one particular note. The simplest of these instruments is the flute (or "Pan's flute"), which usually has about 20 pipes of various lengths, closed at one end and making sounds when blown across the other, open end. The largest and most complex instrument of this type is the organ, containing up to 10,000 pipes, which the organist controls using a complex system of mechanical gears. The organ dates back to ancient times. Clay figurines depicting musicians playing an instrument made of many bellows pipes were made in Alexandria as early as the 2nd century BC. BC. By the X century. organ is being used Christian churches, and treatises written by monks on the structure of organs appear in Europe. According to legend, big organ, built in the X century. for Winchester Cathedral in England, had 400 metal pipes, 26 bellows and two keyboards with 40 keys, where each key controlled ten pipes. Over the following centuries, the device of the organ was improved in mechanical and musically, and already in 1429 an organ with 2500 pipes was built in Amiens Cathedral. Germany towards the end of the 17th century. organs have already acquired their modern form.
An organ installed in 1979 in the Sydney Concert Hall opera house in Australia, is the largest and most technically advanced organ in the world. Designed and built by R. Sharp. It has about 10,500 pipes controlled by a mechanical transmission with five hand and one foot pads. The organ can be controlled automatically by a magnetic tape on which the musician's performance was previously recorded digitally.
Terms used to describe organ devices, reflect their origin from tubular wind instruments into which air was blown by mouth. The tubes of the organ are open from above, and from below they have a narrowed conical shape. Across the flattened part, above the cone, passes the “mouth” of the pipe (cut). A “tongue” (horizontal rib) is placed inside the tube, so that a “labial opening” is formed between it and the lower “lip” ( narrow gap). Air is forced into the pipe by large bellows and enters its cone-shaped base at a pressure of 500 to 1000 pascals (5 to 10 cm of water column). When, when the corresponding pedal and key are pressed, the air enters the pipe, it rushes up, forming upon exiting labial fissure wide flat stream. A jet of air passes across the slot of the "mouth" and, hitting the upper lip, interacts with the air column in the pipe itself; as a result, stable vibrations are created, which make the pipe “speak”. In itself, the question of how this sudden transition from silence to sound occurs in the trumpet is very complex and interesting, but it is not considered in this article. The conversation will mainly be about the processes that ensure the continuous sound of organ pipes and create their characteristic tonality.
The organ pipe is excited by air entering its lower end and forming a jet as it passes through the gap between the lower lip and tongue. In the section, the jet interacts with the air column in the pipe near the upper lip and passes either inside the pipe or outside it. Steady-state oscillations are created in the air column, causing the trumpet to sound. Air pressure, which varies according to the standing wave law, is shown by colored shading. A removable sleeve or plug is mounted on the upper end of the pipe, which allows you to slightly change the length of the air column during adjustment.
It may seem that the task of describing an air jet that generates and preserves the sound of an organ belongs entirely to the theory of fluid and gas flows. It turned out, however, that it is very difficult to theoretically consider the movement of even a constant, smooth, laminar flow, as for a completely turbulent jet of air that moves in an organ pipe, its analysis is incredibly complex. Fortunately, turbulence, which is complex view air movement, actually simplifies the nature of the air flow. If this flow were laminar, then the interaction of the air jet with the environment would depend on their viscosity. In our case, turbulence replaces viscosity as the determining interaction factor in direct proportion to the width of the air stream. During the construction of the organ, special attention is paid to ensuring that the air flows in the pipes are completely turbulent, which is achieved with the help of small cuts along the edge of the tongue. Surprisingly, unlike laminar flow, turbulent flow is stable and can be reproduced.
The fully turbulent flow gradually mixes with the surrounding air. The process of expanding and slowing down is relatively simple. The curve depicting the change in flow velocity depending on the distance from the central plane of its section has the form of an inverted parabola, the top of which corresponds to maximum value speed. The flow width increases in proportion to the distance from the labial fissure. The kinetic energy of the flow remains unchanged, so the decrease in its speed is proportional to the square root of the distance from the slot. This dependence is confirmed by both calculations and experimental results (taking into account a small transition region near the labial gap).
In an already excited and sounding organ pipe, the air flow enters from the labial slit into an intense sound field in the slit of the pipe. The air movement associated with the generation of sounds is directed through the slot and therefore perpendicular to the plane of the flow. Fifty years ago, B. Brown from the College of the University of London managed to photograph the laminar flow of smoky air in the sound field. The images showed the formation of tortuous waves, which increase as they move along the stream, until the latter breaks up into two rows of vortex rings rotating in opposite directions. The simplified interpretation of these and similar observations has led to an incorrect description of the physical processes in organ pipes, which can be found in many textbooks.
A more fruitful method of studying the actual behavior of an air jet in a sound field is to experiment with a single tube in which the sound field is created using a loudspeaker. As a result of such research, carried out by J. Coltman in the laboratory of the Westinghouse Electric Corporation and a group with my participation at the University of New England in Australia, the fundamentals were developed modern theory physical processes occurring in organ pipes. In fact, even Rayleigh gave a thorough and almost complete mathematical description laminar flows of inviscid media. Since it was found that turbulence does not complicate, but simplifies the physical picture of air strings, it was possible to use the Rayleigh method with slight modifications to describe the air flows experimentally obtained and investigated by Coltman and our group.
If there were no labial slot in the tube, then one would expect that the air jet in the form of a strip of moving air would simply move back and forth along with all the other air in the slot of the tube under the influence of acoustic vibrations. In reality, when the jet leaves the slot, it is effectively stabilized by the slot itself. This effect can be compared with the result of imposing on the general oscillatory movement of air in the sound field a strictly balanced mixing localized in the plane of a horizontal edge. This localized mixing, which has the same frequency and amplitude as the sound field, and as a result creates zero mixing of the jet at the horizontal fin, is stored in the moving air flow and creates a sinuous wave.
Five pipes of different designs produce sounds of the same pitch but different timbre. The second trumpet from the left is the dulciana, which has a gentle, subtle sound, reminiscent of the sound of a stringed instrument. The third pipe is an open range, giving light, ringing sound, which is most characteristic of the organ. The fourth trumpet has the sound of a heavily muffled flute. Fifth trumpet - Waldflote ( « forest flute") with a soft sound. The wooden pipe on the left is closed with a plug. It has the same fundamental frequency as the other pipes, but resonates at odd overtones whose frequencies are an odd number of times the fundamental frequency. The length of the remaining pipes is not exactly the same, as "end correction" is made to obtain the same pitch.
As Rayleigh showed for the type of jet he studied, and as we comprehensively confirmed for the case with a divergent turbulent jet, the wave propagates along the flow at a speed slightly less than half the speed of air in the central plane of the jet. In this case, as it moves along the flow, the wave amplitude increases almost exponentially. Typically, it doubles as the wave travels one millimeter, and its effect quickly becomes dominant over the simple reciprocating lateral movement caused by sound vibrations.
It was found that the highest rate of wave growth is achieved when its length along the flow is six times the width of the flow at a given point. On the other hand, if the wavelength is less than the width of the stream, then the amplitude does not increase and the wave may disappear altogether. Since the air jet expands and slows down as it moves away from the gap, only long waves i.e. low frequency vibrations. This circumstance will turn out to be important in the subsequent consideration of the creation of harmonic sounding of organ pipes.
Let us now consider the effect of the sound field of an organ pipe on an air jet. It is easy to imagine that the acoustic waves of the sound field in the pipe slot cause the tip of the air jet to move across the upper lip of the slot, so that the jet is either inside the pipe or outside it. It resembles a picture when a swing is already being pushed. The air column in the pipe is already oscillating, and when the gusts of air enter the pipe in sync with the vibration, they retain their vibratory strength despite the various energy losses associated with sound propagation and air friction against the pipe walls. If the gusts of air do not coincide with the fluctuations of the air column in the pipe, they will suppress these fluctuations and the sound will fade.
The shape of the air jet is shown in the figure as a series of successive frames as it exits the labial slot into a moving acoustic field created in the “mouth” of the tube by an air column that resonates inside the tube. Periodic displacement of air in the section of the mouth creates a tortuous wave moving at a speed half that of air in the central plane of the jet and increasing exponentially until its amplitude exceeds the width of the jet itself. Horizontal sections show the path segments that the wave travels in the jet in successive quarters of the oscillation period. T. The secant lines approach each other as the jet velocity decreases. In the organ pipe, the upper lip is located in the place indicated by the arrow. The air jet alternately exits and enters the pipe.
Measurement of the sound-producing properties of an air jet can be carried out by placing felt or foam wedges at the open end of the pipe to prevent sound, and creating a sound wave of small amplitude using a loudspeaker. Reflected from the opposite end of the pipe, the sound wave interacts with the air jet at the “mouth” section. The interaction of the jet with the standing wave inside the pipe is measured using a portable tester microphone. In this way, it is possible to detect whether the air jet increases or decreases the energy of the reflected wave in the lower part of the pipe. For the trumpet to sound, the jet must increase the energy. The measurement results are expressed in terms of acoustic "conductivity", defined as the ratio of the acoustic flux at the exit from the section « mouth" to the sound pressure directly behind the cut. The conductance value curve for various combinations of air discharge pressure and oscillation frequency has a spiral shape, as shown in the following figure.
The relationship between the occurrence of acoustic oscillations in the pipe slot and the moment when the next portion of the air jet arrives at the upper lip of the slot is determined by the time interval during which the wave in air flow extends from the labial fissure to the upper lip. Organ builders call this distance "undercut". If the "undercut" is large or the pressure (and hence the speed of movement) of the air is low, then the movement time will be large. Conversely, if the "undercut" is small or the air pressure is high, then the travel time will be short.
In order to accurately determine the phase relationship between the fluctuations of the air column in the pipe and the arrival of portions of the air jet on the inner edge of the upper lip, it is necessary to study in more detail the nature of the effect of these proportions on the air column. Helmholtz believed that the main factor here is the amount of air flow delivered by the jet. Therefore, in order for the portions of the jet to communicate as much energy as possible to the oscillating air column, they must arrive at the moment when the pressure near the inner part of the upper lip reaches a maximum.
Rayleigh put forward a different position. He argued that since the slot is located relatively close to the open end of the pipe, the acoustic waves at the slot, which are affected by the air jet, cannot create a lot of pressure. Rayleigh believed that the air flow, entering the pipe, actually encounters an obstacle and almost stops, which quickly creates a high pressure in it, which affects its movement in the pipe. Therefore, according to Rayleigh, the air jet will transfer the maximum amount of energy if it enters the pipe at the moment when not the pressure, but the flow of acoustic waves itself is maximum. The shift between these two maxima is one quarter of the period of oscillation of the air column in the tube. If we draw an analogy with a seesaw, then this difference is expressed in pushing the seesaw when it is at its highest point and has maximum potential energy (according to Helmholtz), and when it is at its lowest point and has maximum speed (according to Rayleigh).
The acoustic conductivity curve of the jet has the shape of a spiral. The distance from the starting point indicates the magnitude of the conductivity, and the angular position indicates the phase shift between the acoustic flow at the outlet of the slot and the sound pressure behind the slot. When the flow is in phase with the pressure, the conductivity values lie in the right half of the helix and the energy of the jet is dissipated. In order for the jet to generate sound, the conductivities must be in the left half of the helix, which occurs when the jet is compensated or phased out with respect to the pressure downstream of the pipe cut. In this case, the length of the reflected wave is greater than the length of the incident wave. The value of the reference angle depends on which of the two mechanisms dominates the excitation of the tube: the Helmholtz mechanism or the Rayleigh mechanism. When the conductivity is in the upper half of the helix, the jet lowers the natural resonant frequency of the pipe, and when the conductivity value is in the lower part of the helix, it raises the natural resonant frequency of the pipe.
The graph of the movement of the air flow in the pipe (dashed curve) at a given jet deflection is not symmetrical with respect to the zero deflection value, since the pipe lip is designed so as to cut the jet not along its central plane. When the jet is deflected along a simple sinusoid with a large amplitude (solid black curve), the air flow entering the tube (color curve) "saturates" first at one extreme point of the jet deflection when it completely exits the tube. With an even greater amplitude, the air flow is also saturated at the other extreme point of deviation, when the jet completely enters the pipe. The displacement of the lip gives the flow an asymmetric waveform, the overtones of which have frequencies that are multiples of the frequency of the deflecting wave.
For 80 years, the problem remained unresolved. Moreover, new studies have not actually been conducted. And only now she has found a satisfactory solution thanks to the work of L. Kremer and H. Leasing from the Institute. Heinrich Hertz in the West. Berlin, S. Eller of the US Naval Academy, Coltman and our group. In short, both Helmholtz and Rayleigh were both partly right. The relationship between the two mechanisms of action is determined by the pressure of the injected air and the frequency of sound, with the Helmholtz mechanism being the main one at low pressures and high frequencies, and the Rayleigh mechanism at high pressures and low frequencies. For organ pipes of standard design, the Helmholtz mechanism usually plays a more important role.
Coltman developed a simple and effective method study of the properties of the air jet, which was somewhat modified and improved in our laboratory. This method is based on the study of the air jet at the slit of the organ pipe, when its far end is closed with felt or foam sound-absorbing wedges that prevent the pipe from sounding. Then, from a loudspeaker placed at the far end, a sound wave is fed down the pipe, which is reflected from the edge of the slot, first with an injected jet, and then without it. In both cases, the incident and reflected waves interact inside the pipe, creating a standing wave. By measuring, with a small probe microphone, changes in wave configuration as the air jet is applied, it can be determined whether the jet increases or decreases the energy of the reflected wave.
In our experiments, we actually measured the "acoustic conductivity" of the air jet, which is determined by the ratio of the acoustic flow at the slot exit, created by the presence of the jet, to the acoustic pressure directly inside the slot. Acoustic conductivity is characterized by magnitude and phase angle, which can be represented graphically as a function of frequency or discharge pressure. If we present a graph of conductivity with an independent change in frequency and pressure, then the curve will have the shape of a spiral (see figure). The distance from the starting point of the helix indicates the conductivity value, and the angular position of the point on the helix corresponds to the phase delay of the sinuous wave that occurs in the jet under the influence of acoustic vibrations in the pipe. A delay of one wavelength corresponds to 360° around the circumference of the helix. Due to the special properties of the turbulent jet, it turned out that when the conductivity value is multiplied by the square root of the pressure value, all the values measured for a given organ pipe fit on the same spiral.
If the pressure remains constant, and the frequency of the incoming sound waves increases, then the points indicating the magnitude of the conductivity approach in a spiral towards its middle in a clockwise direction. At constant frequency and increasing pressure, these points move away from the middle in the opposite direction.
Interior view of the Sydney Opera House organ. Some pipes of its 26 registers are visible. Most of the pipes are made of metal, some are made of wood. The length of the sounding part of the pipe doubles every 12 pipes, and the diameter of the pipe doubles approximately every 16 pipes. Many years of experience of the masters - the creators of organs allowed them to find the best proportions, providing a stable sound timbre.
When the point of conductivity is in the right half of the helix, the jet takes energy from the flow in the pipe, and therefore there is an energy loss. With the position of the point in the left half, the jet will transfer energy to the flow and thereby act as a generator of sound vibrations. When the conductivity value is in the upper half of the helix, the jet lowers the natural resonant frequency of the pipe, and when this point is in the lower half, the jet raises the natural resonant frequency of the pipe. The value of the angle characterizing the phase lag depends on which scheme - Helmholtz or Rayleigh - the main excitation of the pipe is carried out, and this, as was shown, is determined by the pressure and frequency values. However, this angle, measured from the right side of the horizontal axis (right quadrant), is never significantly greater than zero.
Since 360° around the circumference of the helix corresponds to a phase lag equal to the length of the winding wave propagating along the air jet, the magnitude of such a lag from much less than a quarter of the wavelength to almost three-fourths of its length will lie on the spiral from the center line, that is, in that part , where the jet acts as a generator of sound vibrations. We have also seen that, at a constant frequency, the phase lag is a function of the injected air pressure, which affects both the speed of the jet itself and the speed of propagation of the tortuous wave along the jet. Since the speed of such a wave is half the speed of the jet, which in turn is directly proportional to the square root of the pressure, a change in the phase of the jet by half the wavelength is possible only with a significant change in pressure. Theoretically, the pressure can change by a factor of nine before the trumpet stops producing sound at its fundamental frequency, if other conditions are not violated. In practice, however, the trumpet starts sounding at a higher frequency until the specified upper limit of pressure change is reached.
It should be noted that in order to make up for energy losses in the pipe and ensure sound stability, several turns of the helix can go far to the left. Only one more such loop, the location of which corresponds to about three half-waves in the jet, can make the pipe sound. Since the conductance of the strings at this point is low, the sound produced is weaker than any sound corresponding to a point on the outer turn of the helix.
The shape of the conduction helix can become even more complicated if the deviation at the upper lip exceeds the width of the jet itself. In this case, the jet is almost completely blown out of the pipe and blown back into it at each displacement cycle, and the amount of energy that it imparts to the reflected wave in the pipe ceases to depend on a further increase in amplitude. Correspondingly, the efficiency of the air strings in the mode of generating acoustic vibrations also decreases. In this case, an increase in the jet deflection amplitude only leads to a decrease in the conduction helix.
The decrease in jet efficiency with an increase in the deflection amplitude is accompanied by an increase in energy losses in the organ pipe. The fluctuations in the pipe are quickly set to a lower level, at which the energy of the jet exactly compensates for the energy losses in the pipe. It is interesting to note that in most cases the energy losses due to turbulence and viscosity are much higher than the losses associated with the scattering of sound waves through the slot and open ends of the pipe.
Section of an organ pipe of a range type, which shows that the tongue has a notch to create a uniform turbulent movement of the air stream. The pipe is made of "marked metal" - an alloy with a high content of tin and the addition of lead. In the manufacture of sheet material from this alloy, a characteristic pattern is fixed on it, which is clearly visible in the photograph.
Of course, the actual sound of the pipe in the organ is not limited to one specific frequency, but contains sounds of a higher frequency. It can be proved that these overtones are exact harmonics of the fundamental frequency and differ from it by an integer number of times. Under constant air injection conditions, the shape of the sound wave on the oscilloscope remains exactly the same. The slightest deviation of the harmonic frequency from a value that is strictly a multiple of the fundamental frequency leads to a gradual, but clearly visible change in the waveform.
This phenomenon is of interest because the resonant vibrations of the air column in an organ pipe, as in any open pipe, are set at frequencies that are somewhat different from those of the harmonics. The fact is that with an increase in frequency, the working length of the pipe becomes slightly smaller due to a change in the acoustic flux at the open ends of the pipe. As will be shown, overtones in the organ pipe are created by the interaction of the air jet and the lip of the slot, and the pipe itself serves for higher frequency overtones mainly as a passive resonator.
Resonant vibrations in the pipe are created with the greatest movement of air at its holes. In other words, the conductivity in the organ pipe should reach its maximum at the slot. It follows that resonant vibrations also occur in a pipe with an open long end at frequencies at which an integer number of half-waves of sound vibrations fit in the length of the pipe. If we designate the fundamental frequency as f 1 , then higher resonant frequencies will be 2 f 1 , 3f 1 etc. (In fact, as already pointed out, the highest resonant frequencies are always slightly higher than these values.)
In a pipe with a closed or muffled long-range horse, resonant oscillations occur at frequencies at which an odd number of quarters of a wavelength fits in the length of the pipe. Therefore, to sound on the same note, a closed pipe can be half as long as an open one, and its resonant frequencies will be f 1 , 3f 1 , 5f 1 etc.
The results of the effect of changing the pressure of the forced air on the sound in a conventional organ pipe. Roman numerals denote the first few overtones. The main trumpet mode (in color) covers a range of well-balanced normal sounds at normal pressure. As the pressure increases, the sound of the trumpet goes to the second overtone; when the pressure is reduced, a weakened second overtone is created.
Now let's return to the air stream in the organ pipe. We see that high-frequency wave disturbances gradually decay as the jet width increases. As a result, the end of the jet near the upper lip oscillates almost sinusoidally at the fundamental frequency of the sounding of the pipe and almost independently of the higher harmonics of the acoustic field oscillations near the pipe slot. However, the sinusoidal movement of the jet will not create the same movement of the air flow in the pipe, since the flow is “saturated” due to the fact that, with an extreme deviation in any direction, it flows completely either from the inside or from outside upper lip. In addition, the lip is usually somewhat displaced and cuts the flow not exactly along its central plane, so that the saturation is not symmetrical. Therefore, the fluctuation of the flow in the pipe has a complete set of harmonics of the fundamental frequency with a strictly defined ratio of frequencies and phases, and the relative amplitudes of these high-frequency harmonics rapidly increase with increasing amplitude of the air jet deflection.
In a conventional organ pipe, the amount of jet deflection in the slot is commensurate with the width of the jet at the upper lip. As a result, the air flow creates big number overtones. If the lip divided the jet strictly symmetrically, there would be no even overtones in the sound. So usually the lip is given some blending to keep all the overtones.
As you might expect, open and closed pipes produce different sound qualities. The frequencies of the overtones created by the jet are a multiple of the main jet oscillation frequency. A column of air in a pipe will strongly resonate to a certain overtone only if the acoustic conductivity of the pipe is high. In this case, there will be a sharp increase in amplitude at a frequency close to the frequency of the overtone. Therefore, in a closed tube, where only overtones with odd numbers of resonant frequency are created, all other overtones are suppressed. The result is a characteristic "muffled" sound in which even overtones are weak, although not completely absent. On the contrary, an open pipe produces a "lighter" sound, since it retains all the overtones derived from the fundamental frequency.
The resonant properties of a pipe depend to a large extent on energy losses. These losses are of two types: losses due to internal friction and heat transfer, and losses due to radiation through the slot and the open end of the pipe. Losses of the first type are more significant in narrow pipes and at low oscillation frequencies. For wide tubes and at a high oscillation frequency, losses of the second type are significant.
The influence of the location of the lip on the creation of overtones indicates the advisability of shifting the lip. If the lip divided the jet strictly along the central plane, only the sound of the fundamental frequency (I) and the third overtone (III) would be created in the pipe. By shifting the lip, as shown by the dotted line, second and fourth overtones appear, greatly enriching the sound quality.
It follows that for a given length of pipe, and hence a certain fundamental frequency, wide pipes can serve as good resonators only for the fundamental tone and the next few overtones, which form a muffled "flute-like" sound. Narrow tubes serve as good resonators for a wide range of overtones, and since the radiation at high frequencies is more intense than at low frequencies, a high "string" sound is produced. Between these two sounds there is a sonorous juicy sound, which becomes characteristic of a good organ, which is created by the so-called principals or ranges.
In addition, a large organ may have rows of tubes with a conical body, a perforated plug, or other geometric variations. Such designs are intended to modify the resonant frequencies of the trumpet, and sometimes to increase the range of high-frequency overtones in order to obtain a timbre of a special sound coloring. The choice of material from which the pipe is made does not matter much.
There are a large number of possible types of air vibrations in a pipe, and this further complicates the acoustic properties of the pipe. For example, when the air pressure in an open pipe is increased to such an extent that the first overtone will be created in the jet f 1 one quarter of the length of the main wave, the point on the conduction spiral corresponding to this overtone will move to its right half and the jet will cease to create an overtone of this frequency. At the same time, the frequency of the second overtone 2 f 1 corresponds to a half wave in the jet, and it can be stable. Therefore, the sound of the trumpet will go to this second overtone, almost a whole octave above the first, and the exact frequency of oscillation will depend on the resonant frequency of the trumpet and the air supply pressure.
A further increase in discharge pressure can lead to the formation of the next overtone 3 f 1 provided that the "undercut" of the lip is not too large. On the other hand, it often happens that low pressure, insufficient to form the fundamental tone, gradually creates one of the overtones on the second turn of the conduction helix. Such sounds, created with excess or lack of pressure, are of interest for laboratory research, but are used extremely rarely in the organs themselves, only to achieve some special effect.
View of a standing wave at resonance in pipes with an open and closed upper end. The width of each colored line corresponds to the amplitude of vibrations in different parts of the pipe. The arrows indicate the direction of air movement during one half of the oscillatory cycle; in the second half of the cycle, the direction of movement is reversed. Roman numerals indicate harmonic numbers. For an open pipe, all harmonics of the fundamental frequency are resonant. A closed pipe must be half as long to produce the same note, but only the odd harmonics are resonant for it. The complex geometry of the "mouth" of the pipe somewhat distorts the configuration of the waves closer to the lower end of the pipe, without changing them « main » character.
After the master in the manufacture of the organ has made one pipe with the necessary sound, his main and most difficult task is to create the whole series of pipes of the appropriate volume and harmony of sound throughout the entire musical range of the keyboard. This cannot be achieved by a simple set of tubes of the same geometry, differing only in their dimensions, since in such tubes the energy losses from friction and radiation will have a different effect on oscillations of different frequencies. To ensure the constancy of acoustic properties over the entire range, it is necessary to vary a number of parameters. The diameter of the pipe changes with its length and depends on it as a power with an exponent k, where k is less than 1. Therefore, long bass pipes are made narrower. The calculated value of k is 5/6, or 0.83, but taking into account the psychophysical characteristics of human hearing, it should be reduced to 0.75. This value of k is very close to that empirically determined by the great organ makers of the 17th and 18th centuries.
In conclusion, let us consider a question that is important from the point of view of playing the organ: how the sound of many pipes in a large organ is controlled. The basic mechanism of this control is simple and resembles the rows and columns of a matrix. Pipes arranged by registers correspond to the rows of the matrix. All pipes of the same register have the same tone, and each pipe corresponds to one note on the hand or foot keyboard. The air supply to the pipes of each register is controlled by a special lever on which the name of the register is indicated, and the air supply directly to the pipes associated with a given note and constituting a column of the matrix is regulated by the corresponding key on the keyboard. The trumpet will sound only if the lever of the register in which it is located is moved and the desired key is pressed.
The placement of the organ pipes resembles the rows and columns of a matrix. In this simplified diagram, each row, called the register, consists of pipes of the same type, each of which produces one note (the upper part of the diagram). Each column associated with one note on the keyboard (lower part of the diagram) includes pipes different types(left side of the diagram). A lever on the console (right side of the diagram) provides air access to all pipes of the register, and pressing a key on the keyboard blows air into all pipes of a given note. Air access to the pipe is possible only when the row and column are turned on at the same time.
Nowadays, a variety of ways to implement such a circuit can be used using digital logic devices and electrically controlled valves on each pipe. Older organs used simple mechanical levers and reed valves to supply air to the keyboard channels, and mechanical sliders with holes to control the flow of air to the entire register. This simple and reliable mechanical system, in addition to its design advantages, allowed the organist to regulate the speed of opening all the valves himself and, as it were, made this too mechanical musical instrument closer to him.
In the XIX at the beginning of the XX century. large organs were built with all sorts of electromechanical and electropneumatic devices, but recently preference has again been given to mechanical transmissions from keys and pedals, and complex electronic devices are used to simultaneously turn on combinations of registers while playing the organ. For example, the world's largest powered organ was installed in the concert hall of the Sydney Opera House in 1979. It has 10,500 pipes in 205 registers distributed among five hand and one foot keyboards. The key control is carried out mechanically, but it is duplicated by an electrical transmission to which you can connect. In this way, the organist's performance can be recorded in an encoded digital form, which can then be used for automatic playback on the organ of the original performance. The control of registers and their combinations is carried out using electric or electro-pneumatic devices and microprocessors with memory, which allows you to widely vary the control program. Thus, the magnificent rich sound of the majestic organ is created by a combination of the most advanced achievements of modern technology and traditional techniques and principles that have been used by masters of the past for many centuries.
ORGAN, keyboard-wind musical instrument, the largest and most complex instrument in existence. A huge modern organ consists, as it were, of three or more organs, and the performer can control all of them at the same time. Each of the organs that make up such a "large organ" has its own registers (sets of pipes) and its own keyboard (manual). Pipes lined up in rows are located in the internal premises (chambers) of the organ; part of the pipes may be visible, but in principle all pipes are hidden behind a façade (avenue) consisting partly of decorative pipes. The organist sits at the so-called. with a spire (pulpit), in front of it are the keyboards (manuals) of the organ, arranged in terraces one above the other, and under the feet is a pedal keyboard.
Each of the organs included in the "large organ" has its own purpose and name; among the most common are the “main” (German Hauptwerk), “upper”, or “Oberwerk” (German Oberwerk), “ruckpositive” (Rückpositiv), as well as a set of pedal registers. The "main" organ is the largest and contains the main registers of the instrument. "Rukpositive" is similar to "Main", but smaller and softer, and also contains some special solo registers. The "upper" organ adds new solo and onomatopoeic timbres to the ensemble; connected to the pedal are pipes that produce low sounds to enhance the bass lines.
The pipes of some of these organs, especially the "upper" and "ruckpositive", are placed inside semi-closed shutters-chambers, which can be closed or opened with the help of the so-called. channel, resulting in the creation of crescendo and diminuendo effects that are not available on an organ without this mechanism.
In modern organs, air is forced into the pipes by an electric motor; through wooden air ducts, air from the bellows enters the windlads - a system of wooden boxes with holes in the top cover. In these holes they are reinforced with their "legs" organ pipes. From the windlad, air under pressure enters one or another pipe.
Since each pipe is able to reproduce the sound of one pitch and one timbre, a standard five-octave manual requires a set of at least 61 pipes. In general, an organ can have from several hundred to many thousands of tubes. A group of pipes producing sounds of the same timbre is called a register. When the organist turns on the register on the spike (using a button or lever located on the side of the manuals or above them), air is allowed to enter all the pipes of this register. Thus, the performer can choose any register he needs or any combination of registers.
There are different types of pipes that create a variety of sound effects. Pipes are made of tin, lead, copper and various alloys (mainly lead and tin), in some cases wood is also used. The length of the pipes can be from 9.8 m to 2.54 cm or less; the diameter varies depending on the pitch and timbre of the sound. Organ pipes are divided into two groups according to the method of sound production (labial and reed) and into four groups according to timbres. In labial pipes, sound is formed as a result of an air jet hitting the lower and upper lip of the "mouth" (labium) - a cut in the lower part of the pipe; in reed pipes, the source of sound is a metal tongue vibrating under the pressure of an air jet. The main families of registers (timbres) are principals, flutes, gambas and reeds. Principals are the foundation of all organ sounding; flute registers sound calmer, softer and to some extent resemble orchestral flutes in timbre; gambas (strings) are more piercing and sharper than flutes; the timbre of the reeds is metallic, imitating the timbres of orchestral wind instruments. Some organs, especially theater organs, also have percussive timbres, such as imitation cymbals and drums. Finally, many registers are built in such a way that their pipes do not give the main sound, but its transposition by an octave higher or lower, and in the case of the so-called. mixtures and aliquots - not even one sound, as well as overtones to the main tone (aliquots reproduce one overtone, mixtures - up to seven overtones).
The organ is an ancient instrument. Its distant predecessors were, apparently, the bagpipes and Pan's flute. In the 3rd century BC. a water organ appeared - hydraulics; its invention is attributed to the master Ctesibius of Alexandria. The hydraulics was a powerful tool in which the necessary pressure of the air entering the pipes was maintained by a column of water. Gidravlos was used by the Greeks and Romans at hippodromes, in circuses, and also to accompany pagan mysteries. The sound of the hydraulics was unusually strong and piercing. In the first centuries of Christianity, the water pump was replaced by air bellows, which made it possible to increase the size of the pipes and their number in the organ.
Already in the middle of the 5th c. organs were built in Spanish churches, but since the instrument still sounded very loud, it was used only on major holidays. By the 11th century large organs were built throughout Europe; An organ built in 980 in Winchester (England) was known for its extraordinary size. Gradually, the keys were replaced by clumsy large "plates"; the range of the instrument has become wider, the registers have become more diverse. At the same time, a small portable organ - portable and a miniature stationary organ - positive came into wide use.
17th–18th centuries - "golden age" of organ building and organ performance. The organs of this time were distinguished by their beauty and variety of sound; exceptional timbre clarity, transparency made them excellent instruments for performance polyphonic music. Almost all the great organ composers wrote for the "baroque organ", which was more common than the organs of previous and subsequent periods. Romanticism of the 19th century, with its desire for expressive orchestral sound, had a dubious influence on organ building and organ music; the craftsmen tried to create instruments that were an "orchestra for one performer", but as a result, the matter was reduced to a weak imitation of an orchestra. However, in the 19th and 20th centuries many new timbres appeared in the organ, and significant improvements were made in the design of the instrument. The trend towards ever larger organs culminated in the massive 33,112-pipe organ in Atlantic City, New Jersey. This instrument has two pulpits, one of which has seven keyboards. Despite this, in the 20th century. organists and organ builders realized the need to return to simpler and more convenient instrument types.
