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Wow (recording)
Wow is a relatively slow form of flutter (pitch variation) that can affect gramophone records and tape recorders. For both, the collective expression wow and flutter is commonly used. Gramophone records When playing gramophone records, wow is a once-per-revolution pitch variation which could result from warping of the record or from a pressing plate that was not precisely centered. If the grooves are not centered exactly relative to the spindle hole, the linear velocity of the stylus, instead of dropping gradually as the groove spirals towards the center, varies every revolution to be too high (resulting in a higher pitch) when the stylus is further out, and too low when the stylus is further inwards (resulting in a lower pitch). The more eccentric the positioning, the greater the pitch variation. The cause for "wow"-effects on a warped disc is basically the same; a variation in the linear velocity of the stylus relative to the disc. This can be by either radial warping (simil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flutter (electronics And Communication)
In electronics and communication, flutter is the rapid variation of signal parameters, such as amplitude, phase, and frequency. Examples of electronic flutter are: *Rapid variations in received signal levels, such as variations that may be caused by atmospheric disturbances, antenna movements in a high wind, or interaction with other signals. *In radio propagation, a phenomenon in which nearly all radio signals that are usually reflected by ionospheric layers in or above the E-region experience partial or complete absorption. *In radio transmission, rapidly changing signal levels, together with variable multipath time delays, caused by reflection and possible partial absorption of the signal by aircraft flying through the radio beam or common scatter volume. *The variation in the transmission characteristics of a loaded telephone line caused by the action of telegraph direct currents on the loading coils. *In recording and reproducing equipment, the deviation of frequency cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gramophone Record
A phonograph record (also known as a gramophone record, especially in British English), or simply a record, is an analog sound storage medium in the form of a flat disc with an inscribed, modulated spiral groove. The groove usually starts near the periphery and ends near the center of the disc. At first, the discs were commonly made from shellac, with earlier records having a fine abrasive filler mixed in. Starting in the 1940s polyvinyl chloride became common, hence the name vinyl. The phonograph record was the primary medium used for music reproduction throughout the 20th century. It had co-existed with the phonograph cylinder from the late 1880s and had effectively superseded it by around 1912. Records retained the largest market share even when new formats such as the compact cassette were mass-marketed. By the 1980s, digital media, in the form of the compact disc, had gained a larger market share, and the record left the mainstream in 1991. Since the 1990s, records con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tape Recorder
An audio tape recorder, also known as a tape deck, tape player or tape machine or simply a tape recorder, is a sound recording and reproduction device that records and plays back sounds usually using magnetic tape for storage. In its present-day form, it records a fluctuating signal by moving the tape across a tape head that polarizes the magnetic domains in the tape in proportion to the audio signal. Tape-recording devices include the reel-to-reel tape deck and the cassette deck, which uses a cassette for storage. The use of magnetic tape for sound recording originated around 1930 in Germany as paper tape with oxide lacquered to it. Prior to the development of magnetic tape, magnetic wire recorders had successfully demonstrated the concept of magnetic recording, but they never offered audio quality comparable to the other recording and broadcast standards of the time. This German invention was the start of a long string of innovations that have led to present-day magnetic t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitch (music)
Pitch is a perceptual property of sounds that allows their ordering on a frequency-related scale, or more commonly, pitch is the quality that makes it possible to judge sounds as "higher" and "lower" in the sense associated with musical melodies. Pitch is a major auditory attribute of musical tones, along with duration, loudness, and timbre. Pitch may be quantified as a frequency, but pitch is not a purely objective physical property; it is a subjective psychoacoustical attribute of sound. Historically, the study of pitch and pitch perception has been a central problem in psychoacoustics, and has been instrumental in forming and testing theories of sound representation, processing, and perception in the auditory system. Perception Pitch and frequency Pitch is an auditory sensation in which a listener assigns musical tones to relative positions on a musical scale based primarily on their perception of the frequency of vibration. Pitch is closely related to frequency, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capstan (tape Recorder)
A tape transport is the collection of parts of a magnetic tape player or recorder that move the tape and play or record it. Transport parts include the head, capstan, pinch roller, tape pins, and tape guide. The tape transport as a whole is called the ''transport mechanism''. Tape head {{main, Tape head The tape head is the part of a tape recording or playback device which converts the magnetic fluctuations present in the tape into an electrical signal, which is then amplified and sent to speakers or headphones. The tape head is set off-center in a multitrack device in order to record or play one or more tracks running in each direction of the tape (e.g. the two different tracks present on most, if not all, compact cassettes). Capstan The capstan is a rotating spindle used to move recording tape through the mechanism of a tape recorder. The tape is threaded between the capstan and one or more rubber-covered wheels, called pinch rollers, which press against the capstan, thus pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio Cassette
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens and his team at the Dutch company Philips in 1963, Compact Cassettes come in two forms, either already containing content as a prerecorded cassette (''Musicassette''), or as a fully recordable "blank" cassette. Both forms have two sides and are reversible by the user. Although other tape cassette formats have also existed - for example the Microcassette - the generic term ''cassette tape'' is normally always used to refer to the Compact Cassette because of its ubiquity. Its uses have ranged from portable audio to home recording to data storage for early microcomputers; the Compact Cassette technology was originally designed for dictation machines, but improvements in fidelity led to it supplanting the stereo 8-track cartridge and ree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stiction
Stiction is the static friction that needs to be overcome to enable relative motion of stationary objects in contact. The term is a portmanteau of the words ''static'' and ''friction'', and is perhaps also influenced by the verb '' to stick''. Any solid objects pressing against each other (but not sliding) will require some threshold of force parallel to the surface of contact in order to overcome static adhesion. Stiction is a ''threshold'', not a continuous force. However, stiction might also be an illusion made by the rotation of kinetic friction. In situations where two surfaces with areas below the micrometer scale come into close proximity (as in an accelerometer), they may adhere together. At this scale, electrostatic and/or Van der Waals and hydrogen bonding forces become significant. The phenomenon of two such surfaces being adhered together in this manner is also called stiction. Stiction may be related to hydrogen bonding or residual contamination. Automobiles Sticti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Videotape
Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes have also been used for storing scientific or medical data, such as the data produced by an electrocardiogram. Because video signals have a very high bandwidth, and stationary heads would require extremely high tape speeds, in most cases, a helical-scan video head rotates against the moving tape to record the data in two dimensions. Tape is a linear method of storing information and thus imposes delays to access a portion of the tape that is not already against the heads. The early 2000s saw the introduction and rise to prominence of high-quality random-access video recording media such as hard disks and flash memory. Since then, videotape has been increasingly relegated to archival and si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timebase Correction
Time base correction (TBC) is a technique to reduce or eliminate errors caused by mechanical instability present in analog recordings on mechanical media. Without time base correction, a signal from a videotape recorder (VTR) or videocassette recorder (VCR) cannot be mixed with other, more time-stable devices found in television studios and post-production facilities. Most broadcast quality VCRs have simple time base correctors built in though external TBCs are often used. Some high-end domestic analog video recorders and camcorders also include a TBC circuit, which typically can be switched off if required. Time base correction counteracts errors by buffering the video signal as it comes off the videotape at an unsteady rate, and releasing it at a steady rate. TBCs also allow a variable delay in the video stream. By adjusting the rate and delay using a waveform monitor and a vectorscope, the corrected signal can now match the timing of the other devices in the system. If a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Signal Processing
Digital signal processing (DSP) is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations. The digital signals processed in this manner are a sequence of numbers that represent samples of a continuous variable in a domain such as time, space, or frequency. In digital electronics, a digital signal is represented as a pulse train, which is typically generated by the switching of a transistor. Digital signal processing and analog signal processing are subfields of signal processing. DSP applications include audio and speech processing, sonar, radar and other sensor array processing, spectral density estimation, statistical signal processing, digital image processing, data compression, video coding, audio coding, image compression, signal processing for telecommunications, control systems, biomedical engineering, and seismology, among others. DSP can involve linear or nonli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celemony
Celemony Software GmbH is a German musical software company that specializes in digital audio pitch correction software. It produces Melodyne, a popular audio pitch modification tool similar to Auto-Tune, although the program itself is a manual tuning software. History Celemony was founded in October 2000 by Peter Neubäcker, Prof. Dr. Hildegard Sourgens and Carsten Gehle. It is based in Munich, Germany. In 2009, Melodyne won an MIPA Award for Most innovative product. In 2011, Celemony released Capstan, a stand-alone audio restoration software that eliminates wow and flutter from digital recordings. In October 2011, Celemony and PreSonus introduced Audio Random Access (ARA), an extension for audio plug-in formats like AU and VST that permits to exchange data between them which is supported by several DAWs. Melodyne Three years before Celemony was founded, Peter Neubäcker was working on a research experiment with sound. This experiment later turned into the Melodyne pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitch Control
A variable speed pitch control (or vari-speed) is a control on an audio device such as a turntable, tape recorder, or CD player that allows the operator to deviate from a standard speed (such as 33, 45 or even 78 rpm on a turntable), resulting in adjustments in pitch. The latter term "vari-speed" is more commonly used for tape decks, particularly in the UK. Analog pitch controls vary the voltage being used by the playback device; digital controls use digital signal processing to change the playback speed or pitch. A typical DJ deck allows the pitch to be increased or reduced by up to 8%, which is achieved by increasing or reducing the speed at which the platter rotates. Turntable or CD playing speed may be changed for beatmatching and other DJ techniques, while pitch shift using a pitch control has myriad uses in sound recording. Vari-speed in consumer cassette decks Superscope, Inc. of Sun Valley added vari-speed as a feature of portable cassette decks in 1975. The C-1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
