1.
Thaddeus Cahill
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Thaddeus Cahill was a prominent inventor of the early 20th century. He is widely credited with the invention of the first electromechanical musical instrument and he studied the physics of music at Oberlin Conservatory in Oberlin, Ohio. After working as a clerk for Congress in Washington D. C. to pay for his college studies and he became convinced that music could be made with electricity. He showed his first teleharmonium to Lord Kelvin in 1902 and that year he established a laboratory at Holyoke, where he was joined by his brother, Arthur T. Cahill. Cahill had tremendous ambitions for his invention, he wanted music to be broadcast into hotels, restaurants, theaters. At a starting weight of 7 tons and a tag of $200,000. His idea proved to be fruitful, nearly a century later, the Telharmonium, Electricitys Alliance with Music. The American monthly review of reviews, reynold Weidenaar, Magic Music from the Telharmonium, The Scarecrow Press Inc. Electronic Music Interfaces Thaddeus Cahills Telharmonium
2.
Electric organ
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An electronic organ is an electronic keyboard instrument which was derived from the harmonium, pipe organ and theatre organ. Originally, it was designed to imitate the sound of pipe organs, theatre organs, band sounds, or orchestral sounds. In a fashion not totally unlike that of organs, reed organs generated sound by forcing air over a set of reeds by means of a bellows. While reed organs had limited tonal quality, they were small, inexpensive, self-powered, the reed organ was thus able to bring an organlike sound to venues that were incapable of housing or affording pipe organs. This concept was to play an important role in the development of the electric organ, pipe organ In the 1930s, several manufacturers developed electronic organs designed to imitate the function and sound of pipe organs. At the time, some thought that emulation of the pipe organ was the most promising route to take in the development of an electronic organ. Various types of organs have been brought to market over the years. Electricity arrived on the scene in the first decades of the 20th century. Electrically powered reed organs appeared during the first decades of electricity, cahills techniques were later used by Laurens Hammond in his organ design, and the 200-ton Telharmonium served as the worlds first demonstration of electrically produced music on a grand scale. Meanwhile, some experimentation with producing sound by electric impulses was taking place. Built in Belleville, Ontario, the Robb Wave Organ predates its much more successful competitor Hammond by patent and manufacture, the first widespread success in this field was a product of the Hammond Corporation in 1934. The Hammond organ quickly became the successor of the reed organ, from the start, electronic organs operated on a radically different principle from all previous organs. The organ was electrically powered, replacing the reed organs twin bellows pedals with a swell pedal more like that of a pipe organ. Instead of having to pump at a constant rate, as had been the case with the reed organ, from the beginning, the electronic organ had a second manual, also rare among reed organs. The most revolutionary difference in the Hammond, however, was its number of tonewheel settings. By using the drawbars, the organist could combine a variety of tones and harmonics in varying proportions. In all, the Hammond was capable of producing more than 250 million tones, the classic Hammond sound benefitted from the use of free-standing loudspeakers called tone cabinets that produced a higher-quality sound than small built-in speakers. The sound was further enhanced by rotating speaker units, usually manufactured by Leslie
3.
Hammond organ
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The Hammond organ is an electric organ, invented by Laurens Hammond and John M. Hanert and first manufactured in 1935. Various models have been produced, most of use sliding drawbars to create a variety of sounds. Around two million Hammond organs have been manufactured, the organ is commonly used with, and associated with, the Leslie speaker. The organ was originally marketed and sold by the Hammond Organ Company to churches as a lower-cost alternative to the pipe organ. It quickly became popular with jazz musicians in organ trios. Organ trios were hired by jazz club owners, who found that organ trios were a cheaper alternative to hiring a big band. The Hammond Organ Company struggled financially during the 1970s as they abandoned tonewheel organs and these instruments were not as popular with musicians as the tonewheels had been, and the company went out of business in 1985. The Hammond name was purchased by the Suzuki Musical Instrument Corporation and this culminated in the production of the New B-3 in 2002, which provided an accurate recreation of the original B-3 organ using modern digital technology. Hammond-Suzuki continues to manufacture a variety of organs for both players and churches. Other companies, such as Korg, Roland and Clavia, have achieved success in providing emulations of the original tonewheel organs. The sound of a tonewheel Hammond can also be emulated using software such as Native Instruments B4. A number of distinctive Hammond organ features are not usually found on other keyboards like the piano or synthesizer, Some are similar to a pipe organ, but others are unique to the instrument. Most Hammond organs have two 61-note keyboards called manuals, as with pipe organ keyboards, the two manuals are arrayed on two levels close to each other. There is no difference in volume regardless of how heavily or lightly the key is pressed, the keys on each manual have a lightweight action, which allows players to perform rapid passages more easily than on a piano. In contrast to piano and pipe organ keys, Hammond keys have a flat-front profile, Early Hammond console models had sharp edges, but starting with the B-2 these were rounded, as they were cheaper to manufacture. The M series of spinets also had waterfall keys, but later models had diving board style keys which resembled those found on a church organ. Modern Hammond-Suzuki models use waterfall keys, Hammond console organs come with a wooden pedalboard played with the feet, for bass notes. Most console Hammond pedalboards have 25 notes, with the note a low C
4.
Tonewheel
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A tonewheel or tone wheel is a simple electromechanical apparatus for generating electric musical notes in electromechanical organ instruments such as the Hammond Organ. It was invented around 1910 by Rudolph Goldschmidt and was first used in pre vacuum tube radio receivers as a beat frequency oscillator to make continuous wave radiotelegraphy signals audible, the tonewheel assembly consists of a synchronous AC motor and an associated gearbox that drives a series of rotating disks. Each disk has a number of smooth bumps at the rim. As the bump moves past, this effect is reduced again, the magnetic field weakens slightly. Thus, the frequency of the current in the coil depends on the speed of rotation of the disk, a single fundamental frequency can thus be combined with one or more harmonics to produce complex sounds. Tonewheels were first developed for and used in the Telharmonium circa 1896, tonewheel leakage occurs in the Hammond organ and in similar situations, where the large number of tonewheels causes pickups to overhear tonewheels other than their own. This causes the organ to add chromatics to played notes, in some kinds of music this is undesirable, but in others it has become an important part of the Hammond sound. On some digital simulations of Hammond organs tonewheel leakage is a user-set parameter, the tonewheel was invented in 1910 by Rudolph Goldschmidt as a beat frequency oscillator in early radio receivers to make continuous wave radiotelegraphy signals audible. Alexanderson alternator The history of tonewheel
5.
Additive synthesis
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Additive synthesis is a sound synthesis technique that creates timbre by adding sine waves together. The timbre of instruments can be considered in the light of Fourier theory to consist of multiple harmonic or inharmonic partials or overtones. Each partial is a wave of different frequency and amplitude that swells. Additive synthesis most directly generates sound by adding the output of multiple sine wave generators, alternative implementations may use pre-computed wavetables or the inverse Fast Fourier transform. These sinusoids are called harmonics, overtones, or generally, partials, in general, a Fourier series contains an infinite number of sinusoidal components, with no upper limit to the frequency of the sinusoidal functions and includes a DC component. Frequencies outside of the audible range can be omitted in additive synthesis. As a result, only a number of sinusoidal terms with frequencies that lie within the audible range are modeled in additive synthesis. A waveform or function is said to be periodic if y = y for all t, the bandwidth of r k should be significantly less than f 0. Additive synthesis can also produce sounds in which the individual overtones need not have frequencies that are integer multiples of some common fundamental frequency. While many conventional musical instruments have harmonic partials, some have inharmonic partials, inharmonic additive synthesis can be described as y = ∑ k =1 K r k cos , where f k is the constant frequency of k th partial. In the general case, the frequency of a sinusoid is the derivative of the argument of the sine or cosine function. If this frequency is represented in hertz, rather than in angular frequency form and this is the case whether the partial is harmonic or inharmonic and whether its frequency is constant or time-varying. For example, F. Richard Moore listed additive synthesis as one of the four categories of sound synthesis alongside subtractive synthesis, nonlinear synthesis. In this broad sense, pipe organs, which also have pipes producing non-sinusoidal waveforms, summation of principal components and Walsh functions have also been classified as additive synthesis. Modern-day implementations of additive synthesis are mainly digital, Additive synthesis can be implemented using a bank of sinusoidal oscillators, one for each partial. Group additive synthesis is a method to group partials into harmonic groups, an inverse Fast Fourier transform can be used to efficiently synthesize frequencies that evenly divide the transform period or frame. It is possible to analyze the components of a recorded sound giving a sum of sinusoids representation. This representation can be re-synthesized using additive synthesis, one method of decomposing a sound into time varying sinusoidal partials is short-time Fourier transform -based McAulay-Quatieri Analysis
6.
New York City
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The City of New York, often called New York City or simply New York, is the most populous city in the United States. With an estimated 2015 population of 8,550,405 distributed over an area of about 302.6 square miles. Located at the tip of the state of New York. Home to the headquarters of the United Nations, New York is an important center for international diplomacy and has described as the cultural and financial capital of the world. Situated on one of the worlds largest natural harbors, New York City consists of five boroughs, the five boroughs – Brooklyn, Queens, Manhattan, The Bronx, and Staten Island – were consolidated into a single city in 1898. In 2013, the MSA produced a gross metropolitan product of nearly US$1.39 trillion, in 2012, the CSA generated a GMP of over US$1.55 trillion. NYCs MSA and CSA GDP are higher than all but 11 and 12 countries, New York City traces its origin to its 1624 founding in Lower Manhattan as a trading post by colonists of the Dutch Republic and was named New Amsterdam in 1626. The city and its surroundings came under English control in 1664 and were renamed New York after King Charles II of England granted the lands to his brother, New York served as the capital of the United States from 1785 until 1790. It has been the countrys largest city since 1790, the Statue of Liberty greeted millions of immigrants as they came to the Americas by ship in the late 19th and early 20th centuries and is a symbol of the United States and its democracy. In the 21st century, New York has emerged as a node of creativity and entrepreneurship, social tolerance. Several sources have ranked New York the most photographed city in the world, the names of many of the citys bridges, tapered skyscrapers, and parks are known around the world. Manhattans real estate market is among the most expensive in the world, Manhattans Chinatown incorporates the highest concentration of Chinese people in the Western Hemisphere, with multiple signature Chinatowns developing across the city. Providing continuous 24/7 service, the New York City Subway is one of the most extensive metro systems worldwide, with 472 stations in operation. Over 120 colleges and universities are located in New York City, including Columbia University, New York University, and Rockefeller University, during the Wisconsinan glaciation, the New York City region was situated at the edge of a large ice sheet over 1,000 feet in depth. The ice sheet scraped away large amounts of soil, leaving the bedrock that serves as the foundation for much of New York City today. Later on, movement of the ice sheet would contribute to the separation of what are now Long Island and Staten Island. The first documented visit by a European was in 1524 by Giovanni da Verrazzano, a Florentine explorer in the service of the French crown and he claimed the area for France and named it Nouvelle Angoulême. Heavy ice kept him from further exploration, and he returned to Spain in August and he proceeded to sail up what the Dutch would name the North River, named first by Hudson as the Mauritius after Maurice, Prince of Orange
7.
Electronics
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Electronics is the science of controlling electrical energy electrically, in which the electrons have a fundamental role. Commonly, electronic devices contain circuitry consisting primarily or exclusively of active semiconductors supplemented with passive elements, the science of electronics is also considered to be a branch of physics and electrical engineering. The ability of electronic devices to act as switches makes digital information processing possible, until 1950 this field was called radio technology because its principal application was the design and theory of radio transmitters, receivers, and vacuum tubes. Today, most electronic devices use semiconductor components to perform electron control and this article focuses on engineering aspects of electronics. Components are generally intended to be connected together, usually by being soldered to a circuit board. Components may be packaged singly, or in more complex groups as integrated circuits, some common electronic components are capacitors, inductors, resistors, diodes, transistors, etc. Components are often categorized as active or passive, vacuum tubes were among the earliest electronic components. They were almost solely responsible for the revolution of the first half of the Twentieth Century. They took electronics from parlor tricks and gave us radio, television, phonographs, radar, long distance telephony and they played a leading role in the field of microwave and high power transmission as well as television receivers until the middle of the 1980s. Since that time, solid state devices have all but completely taken over, vacuum tubes are still used in some specialist applications such as high power RF amplifiers, cathode ray tubes, specialist audio equipment, guitar amplifiers and some microwave devices. The 608 contained more than 3,000 germanium transistors, thomas J. Watson Jr. ordered all future IBM products to use transistors in their design. From that time on transistors were almost exclusively used for computer logic, circuits and components can be divided into two groups, analog and digital. A particular device may consist of circuitry that has one or the other or a mix of the two types, most analog electronic appliances, such as radio receivers, are constructed from combinations of a few types of basic circuits. Analog circuits use a range of voltage or current as opposed to discrete levels as in digital circuits. The number of different analog circuits so far devised is huge, especially because a circuit can be defined as anything from a single component, analog circuits are sometimes called linear circuits although many non-linear effects are used in analog circuits such as mixers, modulators, etc. Good examples of analog circuits include vacuum tube and transistor amplifiers, one rarely finds modern circuits that are entirely analog. These days analog circuitry may use digital or even microprocessor techniques to improve performance and this type of circuit is usually called mixed signal rather than analog or digital. Sometimes it may be difficult to differentiate between analog and digital circuits as they have elements of both linear and non-linear operation, an example is the comparator which takes in a continuous range of voltage but only outputs one of two levels as in a digital circuit
8.
Loudspeaker
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A loudspeaker is an electroacoustic transducer, which converts an electrical audio signal into a corresponding sound. The most widely used type of speaker in the 2010s is the speaker, invented in 1925 by Edward W. Kellogg. The dynamic speaker operates on the basic principle as a dynamic microphone. Besides this most common method, there are several technologies that can be used to convert an electrical signal into sound. The sound source must be amplified or strengthened with a power amplifier before the signal is sent to the speaker. Speakers are typically housed in an enclosure or speaker cabinet which is often a rectangular or square box made of wood or sometimes plastic. The enclosures materials and design play an important role in the quality of the sound, where high fidelity reproduction of sound is required, multiple loudspeaker transducers are often mounted in the same enclosure, each reproducing a part of the audible frequency range. In this case the individual speakers are referred to as drivers, drivers made for reproducing high audio frequencies are called tweeters, those for middle frequencies are called mid-range drivers, and those for low frequencies are called woofers. Smaller loudspeakers are found in such as radios, televisions, portable audio players, computers. Larger loudspeaker systems are used for music, sound reinforcement in theatres and concerts, the term loudspeaker may refer to individual transducers or to complete speaker systems consisting of an enclosure including one or more drivers. To adequately reproduce a range of frequencies with even coverage, most loudspeaker systems employ more than one driver. Individual drivers are used to different frequency ranges. The drivers are named subwoofers, woofers, mid-range speakers, tweeters, the terms for different speaker drivers differ, depending on the application. In two-way systems there is no mid-range driver, so the task of reproducing the mid-range sounds falls upon the woofer and tweeter, home stereos use the designation tweeter for the high frequency driver, while professional concert systems may designate them as HF or highs. When multiple drivers are used in a system, a network, called a crossover. Loudspeaker driver of the type pictured are termed dynamic to distinguish them from earlier drivers, or speakers using piezoelectric or electrostatic systems, or any of several other sorts. Johann Philipp Reis installed an electric loudspeaker in his telephone in 1861, it was capable of reproducing clear tones, alexander Graham Bell patented his first electric loudspeaker as part of his telephone in 1876, which was followed in 1877 by an improved version from Ernst Siemens. In 1898, Horace Short patented a design for a loudspeaker driven by compressed air, he sold the rights to Charles Parsons
9.
Electromagnetism
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Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually exhibits electromagnetic fields such as fields, magnetic fields. The other three fundamental interactions are the interaction, the weak interaction, and gravitation. The word electromagnetism is a form of two Greek terms, ἤλεκτρον, ēlektron, amber, and μαγνῆτις λίθος magnētis lithos, which means magnesian stone. The electromagnetic force plays a role in determining the internal properties of most objects encountered in daily life. Ordinary matter takes its form as a result of forces between individual atoms and molecules in matter, and is a manifestation of the electromagnetic force. Electrons are bound by the force to atomic nuclei, and their orbital shapes. The electromagnetic force governs the processes involved in chemistry, which arise from interactions between the electrons of neighboring atoms, there are numerous mathematical descriptions of the electromagnetic field. In classical electrodynamics, electric fields are described as electric potential, although electromagnetism is considered one of the four fundamental forces, at high energy the weak force and electromagnetic force are unified as a single electroweak force. In the history of the universe, during the epoch the unified force broke into the two separate forces as the universe cooled. Originally, electricity and magnetism were considered to be two separate forces, Magnetic poles attract or repel one another in a manner similar to positive and negative charges and always exist as pairs, every north pole is yoked to a south pole. An electric current inside a wire creates a corresponding magnetic field outside the wire. Its direction depends on the direction of the current in the wire. A current is induced in a loop of wire when it is moved toward or away from a field, or a magnet is moved towards or away from it. While preparing for a lecture on 21 April 1820, Hans Christian Ørsted made a surprising observation. As he was setting up his materials, he noticed a compass needle deflected away from north when the electric current from the battery he was using was switched on. At the time of discovery, Ørsted did not suggest any explanation of the phenomenon. However, three later he began more intensive investigations
10.
Vacuum tube
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In electronics, a vacuum tube, an electron tube, or just a tube, or valve, is a device that controls electric current between electrodes in an evacuated container. Vacuum tubes mostly rely on thermionic emission of electrons from a hot filament or a cathode heated by the filament and this type is called a thermionic tube or thermionic valve. A phototube, however, achieves electron emission through the photoelectric effect, the simplest vacuum tube, the diode, contains only a heater, a heated electron-emitting cathode, and a plate. Current can only flow in one direction through the device between the two electrodes, as electrons emitted by the travel through the tube and are collected by the anode. Adding one or more control grids within the tube allows the current between the cathode and anode to be controlled by the voltage on the grid or grids, Tubes with grids can be used for many purposes, including amplification, rectification, switching, oscillation, and display. In the 1940s the invention of devices made it possible to produce solid-state devices, which are smaller, more efficient, more reliable, more durable. Hence, from the mid-1950s solid-state devices such as transistors gradually replaced tubes, the cathode-ray tube remained the basis for televisions and video monitors until superseded in the 21st century. However, there are still a few applications for which tubes are preferred to semiconductors, for example, the used in microwave ovens. One classification of vacuum tubes is by the number of active electrodes, a device with two active elements is a diode, usually used for rectification. Devices with three elements are used for amplification and switching. Additional electrodes create tetrodes, pentodes, and so forth, which have additional functions made possible by the additional controllable electrodes. X-ray tubes are vacuum tubes. Phototubes and photomultipliers rely on electron flow through a vacuum, though in those cases electron emission from the cathode depends on energy from photons rather than thermionic emission, since these sorts of vacuum tubes have functions other than electronic amplification and rectification they are described in their own articles. A vacuum tube consists of two or more electrodes in a vacuum inside an airtight enclosure, most tubes have glass envelopes, though ceramic and metal envelopes have been used. The electrodes are attached to leads which pass through the envelope via an airtight seal, Tubes were a frequent cause of failure in electronic equipment, and consumers were expected to be able to replace tubes themselves. In addition to the terminals, some tubes had an electrode terminating at a top cap. The principal reason for doing this was to avoid leakage resistance through the tube base, the bases were commonly made with phenolic insulation which performs poorly as an insulator in humid conditions. There was even a design that had two top cap connections
