Hello, I’m Ginny Moe, this is Adam Sullivan's Music Theory Blog and you're listening to an episode of The Pipe Organ: its development and design.
Last month's episode was on the basic two types of pipes: how they work and how they sound. You can access again it online anytime. This month's episode is on how the organist controls which pipes actually sound at any given moment.
Pipe organs makes sound when air goes to pipes, so we start with the blower, which sends air to a windchest which is attached to every pipe, with most pipes actually sitting right on top. When one pipe is played it doesn't take much air but when many pipes are played at once it takes a lot of air, reducing the air pressure. So the blower sends air to the windchest through a reservoir, which keeps the air at a constant pressure whether one or 100 pipes are sounding. If you look down on the top of the windchest, you can tell it's not just a big balloon with a lot of pipes sticking out haphazardly. The pipes are arranged in rows and columns, with the toe of any pipe fitting into a hole on the windchest through which wind enters the pipe.
Each column on the chest holds a rank, which is a set of pipes of matching design and sound. Each rank has one pipe for each note, and ranks are usually arranged in order on the chest from the lowest and longest pipes at one end to the shortest and highest at the other end. Two ranks of pipes require two columns and two pipes for each note, three ranks require three columns and three pipes, and so on. The rows on the chest correspond to the notes. Each row holds all the pipes which sound a certain note.
On the sides and ends of the windchest are several kinds of machinery controlling tubes of air inside the chest which allow routing of air to various pipes. These controllers are adjusted through linkages to the console, where the organist sits directing air traffic in the windchest.
Modern consoles normally have one pedalboard and several manual keyboards. The pedalboard has 32 keys, arranged like piano keys but bigger, for your feet, the lowest key being two octaves below middle C, the highest the G above middle C. Each manual keyboard has five octaves, starting at the C two octaves below middle C and going up 61 notes to the C three octaves above middle C. In addition, the console has stops, usually on the sides of the manuals, but sometimes above the top manual. And most organs have pistons, which are little buttons below the keyboard and knobs down by the pedals for the feet to play.
Now how does this console give signals to the windchest?
Stops control a channel of air under a rank of pipes. When a stop is engaged, or pulled, by the organist, air flows into the channel and is available for all the pipes in the rank above the channel. If two stops are pulled, air flows into two channels, three stops pulled and air flows into three channels. If many stops are connected to a keyboard, the channels will be dispersed in columns over several windchests for ease maintenance.
Keys control the rows of the windchest, and every pipe designed to sound the note corresponding to a key is in the the entire row controlled by that key. When a key is pressed, pouches under the pipes in the row open, and if air is in a channel under any pipe, the air is released into a pipe sounding a note.
So, for example, a windchest with eight ranks has eight columns corresponding to eight stops on the console, and on manual windchests, it has sixty-one rows corresponding to the sixty-one keys on the manual keyboard, for a total of 488 pipes. When one stop is pulled, and the organist plays one key, the windchest is signaled to send wind to one rank, and one row. Wind is released to the pipe at the intersection of that column and row, and the one pipe sounds. When two keys are played, two pipes get wind, three keys winds three pipes. If another stop is pulled, another channel of air is available, and one key sounds two pipes, one in each rank, the same note, but different in tone quality. Playing two keys sounds two pipes in each rank, playing three keys sounds three pipes in each rank, for a total of six pipes.
The third main control type on the console, ubiquitous in modern pipe organs, is combination action. Most often it is entirely at the console, for it signals several stops to engage (or disengage) simultaneously. Combinations are activated by pressing the pistons underneath the manuals or near the pedals.
To summarize, in a pipe organ, the blower sends air through a reservoir to the windchest. Pipes sit on the chest arranged in columns of ranks and rows of notes. Organists control which pipes sound by sending signals from a console to the windchest. The majority of these signals are of three types: Keys, controlling rows of notes; Stops, controlling columns of ranks, and Pistons, controlling combinations of stops.
That’s all for this episode, I'm Ginny Moe, and this is Adam Sullivan's Music Theory Blog. Thanks to Adam for hosting this series, The Pipe Organ: its development and design. I hope you’ll check in again next month, when we’ll begin looking at how the sound and design of the pipe organ developed throughout history.
That’s all for this episode. I hope you’ll check in again next month, when we’ll begin looking at how the sound and design of the pipe organ developed throughout history. I'm Ginny Moe, and this is Adam Sullivan's Music Theory Blog (sulliadm.blogspot.com). Thanks to Adam for hosting this series, The Pipe Organ: its development and design.
Showing posts with label pipe organs. Show all posts
Showing posts with label pipe organs. Show all posts
Monday, February 23, 2015
Saturday, January 17, 2015
The Pipe Organ: Development and Design
Written by: Ginny Moe
The design and music of the pipe organ are a result of its history as builders responded to changing societal needs but more importantly as organists, composers, and organ builders learned to take advantage of developments in science and industrial techniques. This session is on the two main types of pipes and how they speak, or make sound.
At its most basic the pipe organ is a set of pipes similar to flutes or clarinets through which wind blows to make sound usually musical sound and which, in the modern organ, is controlled by an organist who plays a keyboard shaped like a piano keyboard.
Almost all pipes on the modern organ are of two types. Flue pipes comprise the majority of the pipes, and they are almost always made of either metal or wood with a foot through which air flows into the pipe. Most organs also use reeds (sometimes called reed pipes) in which the speaking mechanism is covered by a boot into which air flows, vibrating a tongue. As an example, I currently play a pipe organ which has 17 sets (ranks) of flue pipes and 4 ranks of reeds, plus some extras which combine several ranks of flue stops.
Now the sounding mechanism of these two types pipes is very different. In the flue pipe air enters the foot of the pipe through a toe and is directed toward the mouth of the pipe by a languid. Air goes outside the pipe at the mouth, and the the speedy air outside the pipe reduces air pressure inside the pipe, drawing the airstream into the pipe. This is the Bernoulli effect in practice; the same reason jets can fly. IT IS THE AIR ITSELF WHICH VIBRATES, setting up sound waves.
By contrast, in the reed pipe a shallot extends into the boot. An aperture in the shallot is covered by a tongue. The boot surrounds this mechanism, and air enters the boot through a toe in the bottom. The wind presses the tongue against the shallot, and the tongues bends to cover the the aperture. The tongue springs back, allowing the wind to enter the shallot, and again the Bernoulli effect is observed, and sound is produced by the vibrating tongue. Here, IT IS THE TONGUE, OR REED ITSELF, WHICH VIBRATES.
Since the wind itself makes the sound in flue pipes, the pipe, which shapes the trajectory of the wind, directly affects the sound, and the most noticeable difference is made by the width of the pipe. Very narrow pipes generally produce more overtones, like bowed string instruments, and are called string pipes. Very fat pipes generally produce fewer overtones, like flutes, and are called flute pipes. And the most important pipes in any organ are the medium width flue pipes, called diapasons or principals. Various modifications around the mouth of the pipe also change the sound. The number of strings, diapasons, and flutes varies, but as an example, my current instrument has three independent string ranks, six independent flute ranks, and seven independent diapason ranks.
The reeds make a very distinctive sound, but most of them sound more like each other than they sound like any flue pipe. Usually they are louder, and the variation in sound is mostly caused by different shaped and length tongues and apertures in the shallot. What are often called reed pipes are properly referred to as resonators, and they amplify and change the sound. They are designed in many inventive and sometimes bizarre shapes, some of which make a difference in the sound quality, or timbre.
To summarize, organ pipes are normally either flue or reed pipes. In flue pipes, the air vibrates, and in reeds, the tongue vibrates. Most organ pipes are flues, and the length and shape of the pipe make changes in timbre, or sound quality. The most important pipes are the principals, or diapasons, and if you think of the sound of a pipe organ, you are probably thinking of the sound of the diapasons. They are of medium width, and the narrow pipes are called string pipes, while the fatter pipes are called flute pipes. A few reeds are usually part of a pipe organ, providing distinctive solo stops and fiery color. In them the sounding mechanism is covered by a boot, inside of which a tongue vibrates against a shallot to produce sound, which is then shaped modified by a resonator.
Check in again next month, when the subject will be organ keys, and various ways the keys control the pipework. I am Ginny Moe, and this is a series on The Pipe Organ, and how its design developed throughout history.
Twitter: @GinnyMoeRHSCwebsite: GinnyMoe.net
The design and music of the pipe organ are a result of its history as builders responded to changing societal needs but more importantly as organists, composers, and organ builders learned to take advantage of developments in science and industrial techniques. This session is on the two main types of pipes and how they speak, or make sound.
At its most basic the pipe organ is a set of pipes similar to flutes or clarinets through which wind blows to make sound usually musical sound and which, in the modern organ, is controlled by an organist who plays a keyboard shaped like a piano keyboard.
Almost all pipes on the modern organ are of two types. Flue pipes comprise the majority of the pipes, and they are almost always made of either metal or wood with a foot through which air flows into the pipe. Most organs also use reeds (sometimes called reed pipes) in which the speaking mechanism is covered by a boot into which air flows, vibrating a tongue. As an example, I currently play a pipe organ which has 17 sets (ranks) of flue pipes and 4 ranks of reeds, plus some extras which combine several ranks of flue stops.
Now the sounding mechanism of these two types pipes is very different. In the flue pipe air enters the foot of the pipe through a toe and is directed toward the mouth of the pipe by a languid. Air goes outside the pipe at the mouth, and the the speedy air outside the pipe reduces air pressure inside the pipe, drawing the airstream into the pipe. This is the Bernoulli effect in practice; the same reason jets can fly. IT IS THE AIR ITSELF WHICH VIBRATES, setting up sound waves.
By contrast, in the reed pipe a shallot extends into the boot. An aperture in the shallot is covered by a tongue. The boot surrounds this mechanism, and air enters the boot through a toe in the bottom. The wind presses the tongue against the shallot, and the tongues bends to cover the the aperture. The tongue springs back, allowing the wind to enter the shallot, and again the Bernoulli effect is observed, and sound is produced by the vibrating tongue. Here, IT IS THE TONGUE, OR REED ITSELF, WHICH VIBRATES.
Since the wind itself makes the sound in flue pipes, the pipe, which shapes the trajectory of the wind, directly affects the sound, and the most noticeable difference is made by the width of the pipe. Very narrow pipes generally produce more overtones, like bowed string instruments, and are called string pipes. Very fat pipes generally produce fewer overtones, like flutes, and are called flute pipes. And the most important pipes in any organ are the medium width flue pipes, called diapasons or principals. Various modifications around the mouth of the pipe also change the sound. The number of strings, diapasons, and flutes varies, but as an example, my current instrument has three independent string ranks, six independent flute ranks, and seven independent diapason ranks.
The reeds make a very distinctive sound, but most of them sound more like each other than they sound like any flue pipe. Usually they are louder, and the variation in sound is mostly caused by different shaped and length tongues and apertures in the shallot. What are often called reed pipes are properly referred to as resonators, and they amplify and change the sound. They are designed in many inventive and sometimes bizarre shapes, some of which make a difference in the sound quality, or timbre.
To summarize, organ pipes are normally either flue or reed pipes. In flue pipes, the air vibrates, and in reeds, the tongue vibrates. Most organ pipes are flues, and the length and shape of the pipe make changes in timbre, or sound quality. The most important pipes are the principals, or diapasons, and if you think of the sound of a pipe organ, you are probably thinking of the sound of the diapasons. They are of medium width, and the narrow pipes are called string pipes, while the fatter pipes are called flute pipes. A few reeds are usually part of a pipe organ, providing distinctive solo stops and fiery color. In them the sounding mechanism is covered by a boot, inside of which a tongue vibrates against a shallot to produce sound, which is then shaped modified by a resonator.
Check in again next month, when the subject will be organ keys, and various ways the keys control the pipework. I am Ginny Moe, and this is a series on The Pipe Organ, and how its design developed throughout history.
Twitter: @GinnyMoeRHSCwebsite: GinnyMoe.net
Tuesday, May 21, 2013
Organs: A Dissertation in Umpteen Parts; Preamble
Hello, and welcome to the Adam Sullivan Music Theory Blog! My name is Dallas. I'm a friend and colleague of Sulli's; he's been trying to get me on here to do a couple series for months now. For various and sundry reasons I never could get around to it, but lo and behold, here I am!
Let me first give an honest disclaimer: this is not really a dissertation in any way. Not officially, at least. However, as you may come to notice while reading through this series, writing such a thing about the pipe organ can make you feel like you're writing a senior thesis.
I'd like to begin with a few vague points about myself... however, there's a time and place for autobiographical ramblings. (Namely my own personal blog, which will come online in tandem with the publication of this series. More on that later!) For know, suffice to say that I'm a young organist/pianist/violist/bassist/random percussion neophyte/composer living in Rock Hill, SC. Music is my lifeblood. And I have quite a lot to say about certain subjects in the musical spectrum in which we all situate ourselves as musicians.
Which brings us to the point at hand! If you hadn't guessed by now, this is going to be a series all about organs. The lauded "King of Instruments," as it were. Pipe organs have been around for several hundred years, and their evolution over that time frame is staggering. Now, with the advances of modern technology, electronic and digitally-sampled organs are vastly popular; there are even digital organs that have sample sets advanced enough to (fairly) convincingly reproduce the sounds (and seconds of acoustical reverb) of famous organs in vast cathedrals such as the great organ of the Cathedral of St. John the Divine in New York City, or the historic and awe-inspiring instrument in the Oude Kerk in Amsterdam. In this series, I am going to walk you through everything I know—and some things I don't know yet, I'm sure—about the world of the organ. My major focus will be on actual pipe organs, but I can promise to include a wealth of information on their increasingly capable digital counterparts.
By the time this series is completed (which is a daunting thought), you will understand the difference between a Principal and a Stopped Diapason. And what all this business about "feet" seems to be (that is to say, what the heck they mean by 8', 4', 2', and so on when naming stops). And why playing middle "c" with a 2 2/3' mutation rank won't do you any good in representing the pitch of ANY "c" at all. You'll know all about resultants and mixtures and celestes and cornets and what is actually meant by stops called such things as "viola," "trumpet," "tuba," and so on. And of course, the most important bit of all: you'll know the storied journey of the pipe organ from antiquity to the present, and just where its perilous path may or may not take it in the days to come.
By the time this series is completed (which is a daunting thought), you will understand the difference between a Principal and a Stopped Diapason. And what all this business about "feet" seems to be (that is to say, what the heck they mean by 8', 4', 2', and so on when naming stops). And why playing middle "c" with a 2 2/3' mutation rank won't do you any good in representing the pitch of ANY "c" at all. You'll know all about resultants and mixtures and celestes and cornets and what is actually meant by stops called such things as "viola," "trumpet," "tuba," and so on. And of course, the most important bit of all: you'll know the storied journey of the pipe organ from antiquity to the present, and just where its perilous path may or may not take it in the days to come.
This series will publish on Thursdays—not on Tuesdays. As it goes on, the specific flow of things may change, but to begin with, I've listed a very general idea of what you can expect to see, and in what order. Note that certain parts, like II and III, may end up being posted in subsections, as they can get to be QUITE long and involved. Furthermore, these labelled parts do not constitute the entirety of the series. There will be rather less specific "filler" posts here and there along the way as I continue in my constant endeavour to raise interest in and awareness of the incredible world of the organ.
I hope you enjoy the adventure we're about to embark upon. If you don't, well... you will be assimilated. But in all honesty, I can not stress the importance of raising awareness of the (pipe) organ within the musical community. Especially the subsection therein that is in my generation; it is up to us to carry the elements of our forebears into the future. If we're not careful, the organ, King of Instruments as it may once have been called, may not make that journey with us.
Thanks for reading. Have an awesome day, and be sure to thank a music educator somewhere.
—
Part I: The Storied Journey [the history and evolution of the pipe organ, and where it stands today]
I hope you enjoy the adventure we're about to embark upon. If you don't, well... you will be assimilated. But in all honesty, I can not stress the importance of raising awareness of the (pipe) organ within the musical community. Especially the subsection therein that is in my generation; it is up to us to carry the elements of our forebears into the future. If we're not careful, the organ, King of Instruments as it may once have been called, may not make that journey with us.
Thanks for reading. Have an awesome day, and be sure to thank a music educator somewhere.
—
Part I: The Storied Journey [the history and evolution of the pipe organ, and where it stands today]
Part II: Anatomy and Physiology 101 [an introduction to the inner structures and workings of pipe organs]
Part III: Divisions Conquered [an in-depth look at the different kinds of pipes found on various instruments]
Part IV: Pulling Out the Stops [an in-depth look at how different kinds of pipes work together... or don't!]
Part V: The Language Barrier [a brief instalment, to include a breakdown of linguistic variations]
Part VI: Anatomy and Physiology 202 [a really in-depth expansion on A&P 101]
Part VII: Literature of the Organ (I) [an introduction to organ music of the Baroque and Classical eras]
Part VIII: Literature of the Organ (II) [an introduction to organ music of the Romantic and early 20th century eras]
Part IX: Literature of the Organ (III) [an introduction to modern organ music]
Part X: The Digital Crux (I) [part one of the subseries devoted to digital organs and their development; introduction to the epic debate of pipes vs. digital sampling]
Part XI: The Organ as a Concert Instrument [a small dissertation of its own, going into the organ's often enigmatic role as a concert instrument]
Part XII: The Organ in Liturgy [everyone's most familiar aspect of organ music: the church]
Part XIII: The Digital Crux (II) [how digital organs relate to the concert hall, as well as the church]
Part XIV: The Digital Crux (III) [the most current advances for digital organs, and how they're starting to overtake even the greatest pipe organs in many ways; further debate on the pipes/digital argument]
Subscribe to:
Posts (Atom)