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Noise Pollution
Published in Subhash Verma, Varinder S. Kanwar, Siby John, Environmental Engineering, 2022
Subhash Verma, Varinder S. Kanwar, Siby John
Sound is the sensation of acoustic waves that develop pressure fluctuations in a medium. Pure sound is described by pressure waves travelling through a medium. These pressure waves are described by their amplitude and their frequency. With reference to Figure 37.1, a pure sound wave can be described as a sinusoidal curve, having positive and negative pressures within one cycle. The number of these cycles per unit time is called the sound frequency, often expressed as cycles per second, or hertz (Hz). A sound wave with a frequency of 1000 Hz, for example, is one in which the pressure wave will pass a given point 1000 times, or 1000 c/s. Typical sounds that healthy human ears hear range from about 15 Hz to about 20000 Hz. Low-frequency sound is deep (low-pitched), while high-frequency sound is high-pitched. For example, middle A on a piano is at a frequency of 440 Hz. Speech is usually in the range of 1000 to 4000 Hz.
Audio in Multimedia
Published in Sreeparna Banerjee, Elements of Multimedia, 2019
Audio is essentially a sound wave; thus, it has normal wave properties like reflection, refraction, and diffraction. A sound wave is characterized by the following physical properties, which will be described in more detail below [1–6]: Amplitude (loudness/intensity): Sound waves can be represented graphically in two dimensions, with time along the independent (x) axis and amplitude along the dependent (y) axis. Sound waves are periodic compressions alternated with rarefactions propagated in time. The square of the amplitude is the intensity. This gives a measure, known as bel, of the loudness of sound in an appropriate dimension.Frequency (pitch): Frequency gives a measure of the rapidity at which the periodic variations of compression and rarefaction occur and is a measure of the pitch of the sound. A high pitch corresponds to high-frequency sound, and vice versa.Envelope (waveform): The evolution of the sound until it dies down generates a form or envelope.
Source Preparation
Published in Sam McGuire, Roy Pritts, Audio Sampling, 2013
The human pitch recognition range is from about 30 Hz to 13 KHz. We can hear beyond these limits, but there is no pitch recognition. There are many things happening around our ears that create changes in pressure, but only those that are repetitious are translated as pitches. If your ear receives a bunch of non-related pressure changes in the range of hearing, it is most likely a form of noise or non-musical sound. If the ear receives a string of pressure changes that focus around a specific frequency, then it will be interpreted as a pitch.
On Determination of Tonic Note for Singers of Indian Music
Published in IETE Technical Review, 2019
Chandrakant J. Gaikwad, Pradip Sircar
Generally, musical sounds can be described by using pitch, intensity (loudness), duration, and timbre. The first three quantities have their physical correlates. That is, pitch is measured in terms of fundamental frequency, loudness is related to the intensity, and duration corresponds to the lifetime of a musical note. Pitch is the perception of the frequency of a note. When voice or instruments produce sound it produces a spectrum consisting of many overtones along with fundamental frequency. This is referred to as color of the tone or timbre. This constitutes the quality of the underlying sound [1,14,18].
Frequencies Wave Sound Particle Swarm Optimisation (FPSO)
Published in Journal of Experimental & Theoretical Artificial Intelligence, 2022
Ahmad K. Al Hwaitat, Rizik M. H. Al-Sayyed, Imad K. M. Salah, Saher Manaseer, Hamed S. Al-Bdour, Sarah E. Shukri
Frequency can be defined as a measurement in cycles per second. Wavelength is the measure of distance from one wave crest to the next wave crest, see Figure 3. When considering sound waves, amplitude is related to loudness of the sound and frequency to pitch. The higher the frequency, the higher the pitch. The speed of the sound can be related to eq. (3),
Making time perception shorter with pitch and interval patterns
Published in Behaviour & Information Technology, 2023
Wanchanok Sunthorn, Cedric Le Mercier, Chaklam Silpasuwanchai
Pitch refers to the frequency of vibration of the sound waves that produce sound (Moore 2012; Dawson et al. 2017). A high frequency sound is perceived as a high pitch, while a low frequency sound is perceived as a low pitch. Since the volume of a sound influences how a person perceives an experience in general, researchers have investigated whether or not pitch influences time perception.