All articles starting with S
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Sound event detection
Sound event detection (SED) is a machine learning task that identifies acoustic events in audio, outputting each event's class label with onset and offset times.
Sound exposure level
Sound exposure level (SEL) is an acoustic measure of the total sound energy of an event, used to compare short loud sounds with longer quieter ones.
Sound film
Sound film: motion pictures with synchronized recorded sound, also called talkies. Key systems were Vitaphone sound-on-disc (1926 Don Juan, 1927 The Jazz Singer) and optical sound-on-film (Movietone, Photophone), which displaced silent cinema by the early 1930s.
Sound from ultrasound
Sound from ultrasound, also called hypersonic sound or the audio spotlight, generates audible sound in air when a modulated ultrasonic beam self-demodulates, staying confined to a narrow, directional beam.
Sound Group
Sound Group (桑德集团), formally Beijing Sound Environmental Protection Group, is a Chinese environmental protection and new energy group founded by Wen Yibo and based in Beijing.
Sound horizon
The sound horizon is the distance sound waves traveled in the primordial plasma before recombination, about 147 Mpc, surviving as the baryon acoustic oscillation scale.
Sound intensity
Sound intensity, also called acoustic intensity, is the time-averaged rate at which sound energy flows through a unit area, a vector quantity expressed in watts per square meter.
Sound intensity probe
A sound intensity probe is a transducer system that measures the directional flow of acoustic energy per unit area, used for noise source mapping and sound power determination.
Sound level meter
A sound level meter, also called a decibel meter or noise meter, is an instrument that measures sound pressure and displays it as a decibel level.
Sound localization
Sound localization: identifying a sound's direction and distance using interaural time and level differences plus pinna spectral (HRTF) cues; duplex theory, precedence effect, hearing-device limits, and animal comparisons.
Sound of Falling
Sound of Falling (In die Sonne schauen) is a 2025 German drama by Mascha Schilinski about four girls on the same Altmark farm across a century; it won the 2025 Cannes Jury Prize and was Germany's 2026 Oscar submission.
Sound of Freedom (film)
Sound of Freedom is a 2023 American drama film directed by Alejandro Monteverde and starring Jim Caviezel as Tim Ballard, a former agent rescuing trafficked children in Colombia.
Sound of Hope: The Story of Possum Trot
Sound of Hope: The Story of Possum Trot is a 2024 Angel Studios faith-based drama directed by Joshua Weigel, starring Nika King and Demetrius Grosse as Donna and W.C. Martin, whose Texas church adopted 77 foster children; it earned $11.7M worldwide and an A+ CinemaScore.
Sound of Metal
Sound of Metal is Darius Marder's 2019 debut drama starring Riz Ahmed as drummer Ruben Stone, who loses his hearing. Premiered at TIFF 2019, released by Amazon in 2020, it won Oscars for Best Sound and Best Film Editing.
Sound of Mull
The Sound of Mull is a narrow sea channel on Scotland's west coast, separating the Isle of Mull from the Morvern peninsula on the mainland.
Sound of My Voice
Sound of My Voice (2011) is an independent drama directed by Zal Batmanglij, co-written with and starring Brit Marling as cult leader Maggie, who claims to be a time traveler from 2054; released by Fox Searchlight in 2012, it grossed $424,088 and led to The OA.
Sound Physicians
Sound Physicians is a physician-led medical group founded in Tacoma, Washington, in 2001 that staffs hospital medicine, emergency medicine, and critical care for hospitals nationwide.
Sound poetry
Sound poetry (German Lautpoesie) is experimental poetry that abandons meaningful words and composes speech sounds for vocal performance, originating in Dada with Hugo Ball in 1916.
Sound power
Sound power, also called acoustic power, is the rate at which a source radiates acoustic energy in watts. Unlike sound pressure, it does not depend on distance or the room.
Sound pressure
Sound pressure, also called acoustic pressure, is the local deviation from ambient pressure caused by a sound wave, measured in pascals and expressed as sound pressure level in decibels.
Sound pressure level
Sound pressure level (SPL) is a logarithmic measure of sound pressure in decibels, referenced to 20 micropascals in air, and the basis of most noise measurement.
Sound recording and reproduction
Sound recording and reproduction, also known as sound reproduction, is the process of capturing sound in a storable form and recreating it later, reaching playback with Edison's phonograph of 1877.
Sound recording copyright symbol
The sound recording copyright symbol, ℗, is the letter P in a circle marking copyright in a sound recording, as distinct from the © mark.
Sound reinforcement system
A sound reinforcement system, also called live sound reproduction, combines microphones, loudspeakers, mixers, signal processors, and power amplifiers to distribute live or pre-recorded sound over a large area.
Sound speed profile
A sound speed profile is a record of how the speed of sound in seawater varies with depth, used in hydrographic surveying to convert acoustic travel times into depths and positions.
Sound stage
A sound stage is a large, soundproofed building on a film studio lot where sets are built and filmed under full control of sound and lighting.
Sound suppression water system
A sound suppression water system is a launch-pad installation that dumps large volumes of water at ignition and liftoff to dampen acoustics and protect the rocket.
Sound system (DJ)
Sound system (DJ): a crew-built rig of turntables, amplifiers and custom speaker stacks, born in 1950s Kingston with Coxsone Dodd and Duke Reid, spread to the UK via the Windrush generation, and central to clash, dubplate and club culture.
Sound Toll
The Sound Toll (Danish: Øresundstolden) was a transit toll Denmark levied on ships passing through the Sound, collected at Helsingør from about 1429 until 1857.
Sound Transit
Sound Transit is the regional public transit agency of the central Puget Sound region in Washington, operating Link light rail, ST Express buses, and Sounder commuter rail.