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Direct Electric Action
Direct electric action is one of various systems used in pipe organs to control the flow of air (wind) into the organ's pipes when the corresponding keys or pedals are depressed. In direct electric action, the valves beneath the pipes are opened directly by electro-magnet solenoids, while with electro-pneumatic action, the electro-magnet's action admits air into a pneumatic or small bellows which in turn operates the pipe's valve. Other types of actions used in pipe organs are tracker action, using mechanical linkage of rods and levers, and tubular-pneumatic action "Tubular-pneumatic action" refers to an apparatus used in many pipe organs built during the late 19th and early 20th centuries. The term "tubular" refers to the extensive use of lead tubing to connect the organ's console to the valves that control ... which utilizes a change of pressure within lead tubing which connects the key to the valve pneumatic. Sources *William H. Barnes ''The Contemporary American Organ'' (1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipe Organs
The pipe organ is a musical instrument that produces sound by driving pressurized air (called ''wind'') through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ''ranks'', each of which has a common timbre and volume throughout the keyboard compass. Most organs have many ranks of pipes of differing timbre, pitch, and volume that the player can employ singly or in combination through the use of controls called stops. A pipe organ has one or more keyboards (called '' manuals'') played by the hands, and a pedal clavier played by the feet; each keyboard controls its own division, or group of stops. The keyboard(s), pedalboard, and stops are housed in the organ's ''console''. The organ's continuous supply of wind allows it to sustain notes for as long as the corresponding keys are pressed, unlike the piano and harpsichord whose sound begins to dissipate immediately after a key is depressed. The smallest porta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electro-magnet
An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire creates a magnetic field which is concentrated in the hole in the center of the coil. The magnetic field disappears when the current is turned off. The wire turns are often wound around a magnetic core made from a ferromagnetic or ferrimagnetic material such as iron; the magnetic core concentrates the magnetic flux and makes a more powerful magnet. The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field. Electromagnets are widely used as components of other electrical devices, such as motors, generators, electromechanical solenoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solenoid
upright=1.20, An illustration of a solenoid upright=1.20, Magnetic field created by a seven-loop solenoid (cross-sectional view) described using field lines A solenoid () is a type of electromagnet formed by a helix, helical coil of wire whose length is substantially greater than its diameter, which generates a controlled magnetic field. The coil can produce a uniform magnetic field in a volume of space when an electric current is passed through it. The term ''solenoid'' was coined in 1823 by André-Marie Ampère. The helical coil of a solenoid does not necessarily need to revolve around a straight-line axis; for example, William Sturgeon's electromagnet of 1824 consisted of a solenoid bent into a horseshoe shape (not unlike an arc spring). Solenoids provide magnetic focusing of electrons in vacuums, notably in television camera tubes such as vidicons and image orthicons. Electrons take helical paths within the magnetic field. These solenoids, focus coils, surround nearly th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electro-pneumatic Action
The electro-pneumatic action is a control system by the mean of air pressure for pipe organs, whereby air pressure, controlled by an electric current and operated by the keys of an organ console, opens and closes valves within wind chests, allowing the pipes to speak. This system also allows the console to be physically detached from the organ itself. The only connection was via an electrical cable from the console to the relay, with some early organ consoles utilizing a separate wind supply to operate combination pistons. Invention Although early experiments with Barker lever, tubular-pneumatic and electro-pneumatic actions date as far back as the 1850s, credit for a feasible design is generally given to the English organist and inventor, Robert Hope-Jones.George Laing Miller (1909). The Recent Revolution in Organ Building'. (also a He overcame the difficulties inherent in earlier designs by including a rotating centrifugal air blower and replacing banks of batteries with a DC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tracker Action
Tracker action is a term used in reference to pipe organs and steam calliopes to indicate a mechanical linkage between keys or pedals pressed by the organist and the valve that allows air to flow into pipe(s) of the corresponding note. This is in contrast to "direct electric action" and "electro-pneumatic action", which connect the key to the valve through an electrical link or an electrically assisted pneumatic system respectively, or "tubular-pneumatic action" which utilizes a change of pressure within lead tubing which connects the key to the valve pneumatic. History Ancient history Organs trace their history as far back as at least the 3rd century BC with an organlike device known as the hydraulis. Also known as a "water organ" or "Roman organ", the hydraulis was an instrument in which water was used as a source of power to push wind through organ pipes. (It is not to be confused with the hydraulic action of a hydraulophone, an instrument that actually uses water to produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubular-pneumatic Action
"Tubular-pneumatic action" refers to an apparatus used in many pipe organs built during the late 19th and early 20th centuries. The term "tubular" refers to the extensive use of lead tubing to connect the organ's console to the valves that control the delivery of "wind" (air under pressure) to the organ's pipes. Many such organs are extant 100 or more years after their construction. Description In any organ, each pipe has a valve located at its foot which responds to the organist's commands from the console's keyboard, pedalboard and stop controls. These valves are contained in windchests upon which the organ's pipework is set. Any type of apparatus that connects an organ's console with its windchest is referred to as its "action". An organ that utilizes tubular-pneumatic action is commonly called a "tubular-pneumatic organ". It seems the first use of this action was in 1851, in Willis' Great Exhibition organ, though it was only very limited. It appears that the first organ usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
