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Bark Scale
The Bark scale is a psychoacoustical scale proposed by Eberhard Zwicker in 1961. It is named after Heinrich Barkhausen who proposed the first subjective measurements of loudness.Zwicker, E. (1961),Subdivision of the audible frequency range into critical bands" ''The Journal of the Acoustical Society of America'', Volume 33, Issue 2, p. 248 (1961) One definition of the term is "...a frequency scale on which equal distances correspond with perceptually equal distances. Above about 500 Hz this scale is more or less equal to a logarithmic frequency axis. Below 500 Hz the Bark scale becomes more and more linear." The scale ranges from 1 to 24 and corresponds to the first 24 critical bands of hearing. It is related to, but somewhat less popular than, the mel scale, a perceptual scale of pitches judged by listeners to be equal in distance from one another. Bark scale critical bands Since the direct measurements of the critical bands are subject to error, the values in this tab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A440
A440 or A-440 may refer to: * A440 (pitch standard) * A440 highway (Australia), a road in Victoria, Australia * Quebec Autoroute 440 (Laval) * Quebec Autoroute 440 (Quebec City) See also * Apollo 440 Apollo 440 (also known as Apollo Four Forty or @440) are a British electronic music group formed in Liverpool in 1990. The group has written, recorded, and produced five studio albums, collaborated with and produced other artists, remixed as ..., an English band * Airbus A400M, a military transport aircraft * Archimedes 440, abbreviated to A440 - one of the Acorn Archimedes range of RISC computers {{Letter-NumberCombDisambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bark Scale
The Bark scale is a psychoacoustical scale proposed by Eberhard Zwicker in 1961. It is named after Heinrich Barkhausen who proposed the first subjective measurements of loudness.Zwicker, E. (1961),Subdivision of the audible frequency range into critical bands" ''The Journal of the Acoustical Society of America'', Volume 33, Issue 2, p. 248 (1961) One definition of the term is "...a frequency scale on which equal distances correspond with perceptually equal distances. Above about 500 Hz this scale is more or less equal to a logarithmic frequency axis. Below 500 Hz the Bark scale becomes more and more linear." The scale ranges from 1 to 24 and corresponds to the first 24 critical bands of hearing. It is related to, but somewhat less popular than, the mel scale, a perceptual scale of pitches judged by listeners to be equal in distance from one another. Bark scale critical bands Since the direct measurements of the critical bands are subject to error, the values in this tab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychoacoustics
Psychoacoustics is the branch of psychophysics involving the scientific study of sound perception and audiology—how humans perceive various sounds. More specifically, it is the branch of science studying the psychological responses associated with sound (including noise, speech, and music). Psychoacoustics is an interdisciplinary field of many areas, including psychology, acoustics, electronic engineering, physics, biology, physiology, and computer science. Background Hearing is not a purely mechanical phenomenon of wave propagation, but is also a sensory and perceptual event; in other words, when a person hears something, that something arrives at the ear as a mechanical sound wave traveling through the air, but within the ear it is transformed into neural action potentials. The outer hair cells (OHC) of a mammalian cochlea give rise to enhanced sensitivity and better frequency resolution of the mechanical response of the cochlear partition. These nerve pulses then travel to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scales
Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number which scales, or multiplies, some quantity * Long and short scales, how powers of ten are named and grouped in large numbers * Scale parameter, a description of the spread or dispersion of a probability distribution * Feature scaling, a method used to normalize the range of independent variables or features of data * Scale (analytical tool) Measurements * Scale (map), the ratio of the distance on a map to the corresponding actual distance * Weighing scale, an instrument used to measure mass * Scale (ratio), the ratio of the linear dimension of the model to the same dimension of the original * Spatial scale, a classification of sizes * Scale ruler, a tool for measuring lengths and transferring measurements at a fixed ratio of length * Verni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Bands
In audiology and psychoacoustics the concept of critical bands, introduced by Harvey Fletcher in 1933 and refined in 1940, describes the frequency bandwidth of the "auditory filter" created by the cochlea, the sense organ of hearing within the inner ear. Roughly, the critical band is the band of audio frequencies within which a second tone will interfere with the perception of the first tone by auditory masking. Psychophysiologically, beating and auditory roughness sensations can be linked to the inability of the auditory frequency-analysis mechanism to resolve inputs whose frequency difference is smaller than the critical bandwidth and to the resulting irregular "tickling" of the mechanical system (basilar membrane) that resonates in response to such inputs. Critical bands are also closely related to auditory masking phenomena – reduced audibility of a sound signal when in the presence of a second signal of higher intensity within the same critical band. Masking phenomena have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equivalent Rectangular Bandwidth
The equivalent rectangular bandwidth or ERB is a measure used in psychoacoustics, which gives an approximation to the bandwidths of the filters in human hearing, using the unrealistic but convenient simplification of modeling the filters as rectangular band-pass filters, or band-stop filters, like in tailor-made notched music training (TMNMT). Approximations For moderate sound levels and young listeners, the bandwidth of human auditory filters can be approximated by the polynomial equation: where ''f'' is the center frequency of the filter in kHz and ERB(''f'') is the bandwidth of the filter in Hz. The approximation is based on the results of a number of published simultaneous masking experiments and is valid from 0.1 to 6.5 kHz.B.C.J. Moore and B.R. Glasberg, "Suggested formulae for calculating auditory-filter bandwidths and excitation patterns" Journal of the Acoustical Society of America 74: 750-753, 1983. The above approximation was given in 1983 by Moore and Glasber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fletcher–Munson Curves
An equal-loudness contour is a measure of sound pressure level, over the frequency spectrum, for which a listener perceives a constant loudness when presented with pure steady tones. The unit of measurement for loudness levels is the phon and is arrived at by reference to equal-loudness contours. By definition, two sine waves of differing frequencies are said to have equal-loudness level measured in phons if they are perceived as equally loud by the average young person without significant hearing impairment. The Fletcher–Munson curves are one of many sets of equal-loudness contours for the human ear, determined experimentally by Harvey Fletcher and Wilden A. Munson, and reported in a 1933 paper entitled "Loudness, its definition, measurement and calculation" in the ''Journal of the Acoustical Society of America''. Fletcher–Munson curves have been superseded and incorporated into newer standards. The definitive curves are those defined in ISO 226 from the International Organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity Function
A luminous efficiency function or luminosity function represents the average spectral sensitivity of human visual perception of light. It is based on subjective judgements of which of a pair of different-colored lights is brighter, to describe relative sensitivity to light of different wavelengths. It is not an absolute reference to any particular individual, but is a standard observer representation of visual sensitivity of theoretical human eye. It is valuable as a baseline for experimental purposes, and in colorimetry. Different luminous efficiency functions apply under different lighting conditions, varying from photopic in brightly lit conditions through mesopic to scotopic under low lighting conditions. When not specified, ''the luminous efficiency function'' generally refers to the photopic luminous efficiency function. The CIE photopic luminous efficiency function or is a standard function established by the Commission Internationale de l'Éclairage (CIE) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second. It is named after Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. Hertz are commonly expressed in multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation of the energy of a photon, via the Planck relation ''E'' = ''hν'', where ''E'' is the photon's energy, ''ν'' is its freq ... [...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] |
Psychoacoustics
Psychoacoustics is the branch of psychophysics involving the scientific study of sound perception and audiology—how humans perceive various sounds. More specifically, it is the branch of science studying the psychological responses associated with sound (including noise, speech, and music). Psychoacoustics is an interdisciplinary field of many areas, including psychology, acoustics, electronic engineering, physics, biology, physiology, and computer science. Background Hearing is not a purely mechanical phenomenon of wave propagation, but is also a sensory and perceptual event; in other words, when a person hears something, that something arrives at the ear as a mechanical sound wave traveling through the air, but within the ear it is transformed into neural action potentials. The outer hair cells (OHC) of a mammalian cochlea give rise to enhanced sensitivity and better frequency resolution of the mechanical response of the cochlear partition. These nerve pulses then travel to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scale (music)
In music theory, a scale is any set of musical notes ordered by fundamental frequency or pitch. A scale ordered by increasing pitch is an ascending scale, and a scale ordered by decreasing pitch is a descending scale. Often, especially in the context of the common practice period, most or all of the melody and harmony of a musical work is built using the notes of a single scale, which can be conveniently represented on a staff with a standard key signature. Due to the principle of octave equivalence, scales are generally considered to span a single octave, with higher or lower octaves simply repeating the pattern. A musical scale represents a division of the octave space into a certain number of scale steps, a scale step being the recognizable distance (or interval) between two successive notes of the scale. However, there is no need for scale steps to be equal within any scale and, particularly as demonstrated by microtonal music, there is no limit to how many notes can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
