A valve microphone is a condenser microphone which uses a valve amplifier rather than a transistor circuit. [1]
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A valve microphone is a condenser microphone which uses a valve amplifier rather than a transistor circuit. [1]
Microphones have been in use since the early telephone technology of the mid 1800s. However, they achieved higher sound quality in the 1920s with the first double-button carbon mics made by Western Electric. The 387 model, with its 0.0017 inch thick gold-sputtered diaphragm, was the best among these early designs. It was followed by the improved model 600 in the early 1930s, and the double-button became recognised worldwide as a standard in broadcasting. [2]
Vacuum tube or electronic valve amplifiers were first used to resolve microphone impedance and output problems. Bell Labs invented[ citation needed ] the condenser microphone in 1917, and this type of microphone went through many stages of improvement. Due to the invention of valve amplifiers, the production of simple moving coil mics like the Western Electric-designed 630A "8 Ball" became possible. This dynamic microphone went on to become one of the mainstays of American microphone production. In this period, valves were also incorporated internally into microphones, and valve microphones were commercially available as a result.
In the late 1920s, Dr. Harry F. Olson of RCA began developing the ribbon microphone, eventually using permanent magnets. In 1931, nine months after the introduction of Western's 618 dynamic, R.C.A. marketed a bi-directional ribbon microphone, the 44-A. The smooth, less sibilant sound of the ribbon and its elegant styling made it the standard for broadcasters into the 1940s. The design was updated with improved magnetic material in the mid thirties with the 44-B/-BX, which maintained its production until the mid 1950s. Ribbon microphones are still in demand today and come in many styles.
In June 1948, the Neumann U 47 was introduced, and distributed by Telefunken. The U47 was the first condenser microphone switchable between cardioid and omni-directional pick-up patterns. It incorporated the highly successful 12-micron-thick M7 capsule and VF-14 tube amplifier, which was a metal-clad pre-World War II pentode changed to work as a triode. These microphones had evolved from the 1928 CMV3 "bottle" mic, followed by the CMV3A which had interchangeable condenser heads. This mic was notoriously made use of by Hitler at the Berlin Olympics and at Nazi party rallies, and represented the state of the art in microphone technology at that time. [3]
In 1958, Neumann took over the sale of their own mics from Telefunken and made many small changes to the U47 design; however, this mic perhaps more than any other, embodies the valve or tube sound. The design was perishable, so very few remain; therefore, it has become the most sought-after of studio microphones, although many clones and similar versions are now popular.
There are many reasons why valve microphones have become so important in today's recording and home studios. Partly, they are fashionable due to their early use by influential composers and musicians such as the Beatles, Pink Floyd, the Rolling Stones, etc. But also, the sound quality they reproduce has pleasing sonic qualities, even though more technically perfect reproduction is possible with transistor microphones which have less self-noise. [4]
The nuvistor is a type of vacuum tube announced by RCA in 1959. Nuvistors were made to compete with the then-new bipolar junction transistors, and were much smaller than conventional tubes of the day, almost approaching the compactness of early discrete transistor casings. Due to their small size, there was no space to include a vacuum fitting to evacuate the tube; instead, nuvistors were assembled and processed in a vacuum chamber with simple robotic devices. The tube is made entirely of metal with a ceramic base. Triodes and a few tetrodes were made; Nuvistor tetrodes were taller than their triode counterparts.
A microphone, colloquially called a mic, is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, and radio and television broadcasting. They are also used in computers and other electronic devices, such as mobile phones, for recording sounds, speech recognition, VoIP, and other purposes, such as ultrasonic sensors or knock sensors.
An audio power amplifier is an electronic amplifier that amplifies low-power electronic audio signals, such as the signal from a radio receiver or an electric guitar pickup, to a level that is high enough for driving loudspeakers or headphones. Audio power amplifiers are found in all manner of sound systems including sound reinforcement, public address, home audio systems and musical instrument amplifiers like guitar amplifiers. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers.
A recording studio is a specialized facility for recording and mixing of instrumental or vocal musical performances, spoken words, and other sounds. They range in size from a small in-home project studio large enough to record a single singer-guitarist, to a large building with space for a full orchestra of 100 or more musicians. Ideally, both the recording and monitoring spaces are specially designed by an acoustician or audio engineer to achieve optimum acoustic properties.
An instrument amplifier is an electronic device that converts the often barely audible or purely electronic signal of a musical instrument into a larger electronic signal to feed to a loudspeaker. An instrument amplifier is used with musical instruments such as an electric guitar, an electric bass, electric organ, electric piano, synthesizers and drum machine to convert the signal from the pickup or other sound source into an electronic signal that has enough power, due to being routed through a power amplifier, capable of driving one or more loudspeaker that can be heard by the performers and audience.
A guitar amplifier is an electronic device or system that strengthens the electrical signal from a pickup on an electric guitar, bass guitar, or acoustic guitar so that it can produce sound through one or more loudspeakers, which are typically housed in a wooden cabinet. A guitar amplifier may be a standalone wood or metal cabinet that contains only the power amplifier circuits, requiring the use of a separate speaker cabinet–or it may be a "combo" amplifier, which contains both the amplifier and one or more speakers in a wooden cabinet. There is a wide range of sizes and power ratings for guitar amplifiers, from small, lightweight "practice amplifiers" with a single 6-inch speaker and a 10-watt amp to heavy combo amps with four 10-inch or four 12-inch speakers and a 100-watt amplifier, which are loud enough to use in a nightclub or bar performance.
A valve amplifier or tube amplifier is a type of electronic amplifier that uses vacuum tubes to increase the amplitude or power of a signal. Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers in the 1960s and 1970s. Valve amplifiers can be used for applications such as guitar amplifiers, satellite transponders such as DirecTV and GPS, high quality stereo amplifiers, military applications and very high power radio and UHF television transmitters.
Phantom power, in the context of professional audio equipment, is DC electric power equally applied to both signal wires in balanced microphone cables, forming a phantom circuit, to operate microphones that contain active electronic circuitry. It is best known as a convenient power source for condenser microphones, though many active direct boxes also use it. The technique is also used in other applications where power supply and signal communication take place over the same wires.
A ribbon microphone, also known as a ribbon velocity microphone, is a type of microphone that uses a thin aluminum, duraluminum or nanofilm of electrically conductive ribbon placed between the poles of a magnet to produce a voltage by electromagnetic induction. Ribbon microphones are typically bidirectional, meaning that they pick up sounds equally well from either side of the microphone.
A boundary microphone is one or more small omnidirectional or cardioid condenser mic capsule(s) positioned near or flush with a boundary (surface) such as a floor, table, or wall. The capsule(s) are typically mounted in a flat plate or housing. The arrangement provides a directional half-space pickup pattern while delivering a relatively phase-coherent output signal.
Georg Neumann GmbH is a manufacturer of professional recording microphones. It was founded in by Georg Neumann in 1928 and is based in Berlin, Germany. Their best-known products are condenser microphones for recording, broadcast, and live music production purposes. For several decades Neumann was also a leading manufacturer of cutting lathes for phonograph disks, and even ventured into the field of mixing desks. Today Neumann also manufactures preamplifiers, studio monitors, headphones, and audio interfaces.
A valve audio amplifier (UK) or vacuum tube audio amplifier (US) is a valve amplifier used for sound reinforcement, sound recording and reproduction.
Schalltechnik Dr.-Ing. Schoeps GmbH, known as Schoeps Mikrofone, is a German manufacturer of professional studio condenser microphones for recording and broadcast. The privately owned company is based in Karlsruhe, south-west Germany, and was founded in 1948.
An antique radio is a radio receiving set that is collectible because of its age and rarity.
The Neumann U 47 is a large-diaphragm condenser microphone. It is one of the most famous studio microphones and was Neumann's first microphone after the Second World War. The original series, manufactured by Georg Neumann GmbH between 1949 and 1965, employed a tube design; early U 47s used the M 7 capsule, then replaced by the K 47 from 1958. Units produced before 1950 were distributed by Telefunken and bear the Telefunken logo.
Distortion and overdrive are forms of audio signal processing used to alter the sound of amplified electric musical instruments, usually by increasing their gain, producing a "fuzzy", "growling", or "gritty" tone. Distortion is most commonly used with the electric guitar, but may also be used with other electric instruments such as electric bass, electric piano, synthesizer and Hammond organ. Guitarists playing electric blues originally obtained an overdriven sound by turning up their vacuum tube-powered guitar amplifiers to high volumes, which caused the signal to distort. While overdriven tube amps are still used to obtain overdrive, especially in genres like blues and rockabilly, a number of other ways to produce distortion have been developed since the 1960s, such as distortion effect pedals. The growling tone of a distorted electric guitar is a key part of many genres, including blues and many rock music genres, notably hard rock, punk rock, hardcore punk, acid rock, and heavy metal music, while the use of distorted bass has been essential in a genre of hip hop music and alternative hip hop known as "SoundCloud rap".
AKG Acoustics is an acoustics engineering and manufacturing company. It was founded in 1947 by Rudolf Görike and Ernest Plass in Vienna, Austria. It is a part of Harman International Industries, a subsidiary of Samsung Electronics since 2017.
Røde Microphones is an Australian audio technology company that designs and manufactures microphones, headphones, related accessories, audio interfaces, and audio software. It is recognized as a world leader in several audio categories, spanning consumer, producer, and professional markets, specializing in products for music recording, location sound recordings, broadcast and podcasting, filmmaking, and content creation.
Tube sound is the characteristic sound associated with a vacuum tube amplifier, a vacuum tube-based audio amplifier. At first, the concept of tube sound did not exist, because practically all electronic amplification of audio signals was done with vacuum tubes and other comparable methods were not known or used. After introduction of solid state amplifiers, tube sound appeared as the logical complement of transistor sound, which had some negative connotations due to crossover distortion in early transistor amplifiers. However, solid state amplifiers have been developed to be flawless and the sound is later regarded neutral compared to tube amplifiers. Thus the tube sound now means 'euphonic distortion.' The audible significance of tube amplification on audio signals is a subject of continuing debate among audio enthusiasts.
The Sennheiser MD 421 is a German cardioid dynamic microphone, widely used for speech in broadcasting and for music in live concerts and the recording studio. Introduced in 1960, the internal large-diaphragm transducer element of the MD 421 is still produced unchanged by Sennheiser. The MD 421 is considered a classic, an industry standard. More than 500,000 units have been sold.