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W Abbreviation for watt.
W3 An abbreviation for World Wide Web.
Wachner, Brian Gary (1945-1997) American engineer and founder of BGW Systems.
wah-wah pedal (also wa-wa pedal) Music special effects. An electric guitar effects foot pedal that alters the sound in a wavering manner sounding somewhat like the human voice saying the word "wah." Made famous by Jimi Hendrix (and others) in the 1960s using an original Cry Baby pedal. In brass instruments, mostly trumpets, a similar sound is created by covering and uncovering the bell with a rubber toilet plunger. [Hit the link to read its fascinating history.]
waisted drum See: talking drum.
Walker, Peter J. (1916-2003) British engineer and inventor known as the founder of the legendary British audio company Quad.
walla The film industry term for background crowd noises in a movie.
Walla Walla A city in southeast Washington near the Oregon border south-southwest of Spokane. Founded in 1856 near the site of an army fort, it is a manufacturing center in an agricultural region famous for sweet yellow onions and world-class wineries. In spite of its name, a quiet community.
Wall of Sound One of the most famous PA systems of all time, developed and used by the Grateful Dead in the early '70s. Diagram here.
wall-of-sound fire extinguisher A new system developed by DARPA (Defense Advanced Research Projects Agency) that uses sound to steer, thin and even extinguish flames. Hit the link and watch the quickie 10-second video.
Wally Award given at LDI (Live Design International) trade show each year since its inception in 1992, named after Wally Russell. The full name is the Wally Russell Lifetime Achievement Award.
Walkman® Registered trademark of the Sony Corporation originally for their portable audio cassette player. While Philips Norelco's Carry-Coder was first, Sony's Walkman's size and sound quality changed everything in 1979.
Walsh driver Loudspeakers. A novel omnidirectional loudspeaker invented by Lincoln Walsh and granted U.S. Patent 3,424,873 in 1969 (filled in 1964). Called a coherent-sound loudspeaker, a Walsh driver is an inverted-cone that radiates sound all around "... by means of a conical diaphragm operating as a wave transmission line." It is claimed to "... obtain full frequency range, high quality sound omnidirectionally from a single radiator." [US Patent 3,424,873]. Walsh's invention led to the founding of Ohm Acoustics, the exclusive manufacturer of loudspeakers based on Walsh drivers, and whose President/Chief Engineer, John Strohbeen further developed Walsh's concepts (U.S. Patent 4,483,015, et. al.) into what they are today. Also see refinements done by Peter Dick (DDD - Dick's dipole driver).
Walsh, Lincoln (1903-1971) American engineer who developed the Walsh Driver and much more.
Waltzing Matilda Song penned by Banjo Paterson which became Australia's unofficial national anthem. Hit the link for the whole fantastic story.
WAM (Women's Audio Mission) San Francisco-based, non-profit organization dedicated to the advancement of women in music production and the recording arts.
WAN (wide area network) A computer and voice network bigger than a city or metropolitan area.
Wanderlust Festival Held in various cities across the U.S., this festival combines yoga (first) with music, food, wine, crafts, and outdoor adventures.
Wangemann, Theo (1855-1906) German engineer who emigrated to the United States and became Edison's assistant and is recognized as the first professional recording engineer. His work includes a surviving phonograph recording of German chancellor Otto von Bismarck done during the Paris World's Fair in 1889.
warble tone Test Equipment. An amplitude modulated test tone originally used for making acoustic measurements in loudspeaker enclosures; also used in room measurements. "The frequency of the oscillator is swept slowly from the lowest to the highest frequency while being warbled at the rate of four times per second over a range of 10 percent plus and minus the mean frequency." [Audio Cyclopedia] Use of a warbled tone helps prevent standing waves within the space measured.
Warlocks The original name of the band that evolved into The Grateful Dead.
Warner, Harry Morris (1881-1958), Albert (1883-1967) and Samuel L. (1887-1927) were American filmmakers who founded Warner Brothers Pictures, which produced the first talkie, The Jazz Singer (1927), and many film classics, including Casablanca (1942). [AHD]
warp marker Music Software. A method that attaches a position in a music sample to a particular time in the song. It forces the software to arrive at a specific point in the music sample at a specific time.
WASC ( Western Association of Schools and Colleges) One of the six regional associations that accredit public and private colleges and schools in the United States.
waterfall display (aka cumulative spectral decay) Loudspeakers. A two-dimensional, three-coordinate graph displaying frequency on the horizontal, amplitude on the vertical and time on the third leg, back-to-front. Used to display information about a loudspeaker's impulse response. This plot technique is first described and named by M. Bernam and L. Fincham in their paper, "The Application of Digital Techniques to the Measurement of Loudspeakers," Jour. AES Soc., vol. 25, no. 6, 1977, pp. 370-384, where they apply modern DSP techniques to make practical the original work done by D. E. L. Shorter in 1946 ("Loudspeaker Transient Response — Its Measurement and Graphical Representation," B.B.C. Quart., vol. 1, p. 121 (1946).
watermarking 1. Paper The act of adding a translucent design impressed on paper during manufacture and visible when the paper is held to the light. [AHD] 2. Audio or video Embedded data code within the digitized audio or video image that can be recovered but which will not affect the quality of the product. Various methods exist, but all consist of very short (2-5 microseconds long) pieces of code containing all the relevant data about the copyright owner and performance royalties. All make use of the science of steganography.
watt Abbr. W Electricity An International System unit of power equal to one joule per second. (After James Watt.) [AHD]
Watt, James (1736-1819) British engineer and inventor who made fundamental improvements in the steam engine, resulting in the modern, high-pressure steam engine (patented 1769). [AHD]
watts rms No such thing. See apparent power and rms power.
.WAV File extension for a Wave file, the Microsoft format that is the de facto audio file format for PCs.
wave Acoustics. A disturbance which is propagated in a medium in such a manner that, at any point in the medium, the quantity serving as measure of the disturbance is a function of time, while at any instant the displacement at a point is a function of the position of the point. [Harris]
WAVE (Women in AV) Organization that "Promotes collaboration, sharing of ideas, and brainstorming about all things AV" plus 10 other points. Click the link to read all.
wave field synthesis Abbr. WFS "A means by which a soundfield can be reconstructed within a listening area using an array of loudspeakers, enabling faithful spatial reproduction." From "Wavefield Synthesis," J. Audio Eng. Soc., Vol. 52, No. 5, May 2004, pp. 538-543. See also AES Monograph: Wave Field Synthesis by Diemer de Vries.
wavefront Acoustics. Of a progressive wave in space, a continuous surface where the phase is the same at a given instant. [Harris]
Wavefront Festival Three-day electronic dance music festival held at Chicago's Montrose Beach.
Wave-Gotik-Treffen A multi-day yearly festival held in Leipzig, Germany featuring "dark" music, costumes and arts.
wavelength Symbol λ (Greek lower-case lambda) The distance between one peak or crest of a sine wave and the next corresponding peak or crest. The wavelength of any frequency may be found by dividing the speed of sound by the frequency.
wavelet Mathematics. An algorithm used to efficiently compress and decompress the phase and frequency information contained in a transmitted signal.
wax a disc To make a recording. [Decharne]
Weber, Dr. Walter (1907-1940) German engineer best know for his application of AC tape bias to ferrite-oxide tape.
Weber, Wilhelm Eduard (1804-1891), German physicist famous for his study of the electrical structure of matter. The International System unit of magnetic flux is named after him.
Webcast The real time (continuous stream) delivery of audio and video from a server to a client. [Think broadcast]
weber Abbr. Wb The International System unit of magnetic flux, equal to the flux that produces in a circuit of one turn an electromotive force of one volt, when the flux is uniformly reduced to zero within one second. After Wilhelm Eduard Weber. [AHD]
Web ring A group of websites all sharing a common theme. For example, web rings exist for fans of certain bands, movies, TV shows, authors, race car drivers, etc. Soon we will have a web ring for web rings.
Webster, Arthur G. (1863-1923) American scientist who developed the concept of acoustic impedance in 1919 and also contributed to the theory of horn loudspeakers.
wedge loudspeaker also monitor loudspeaker Live Sound. The nickname for a loudspeaker used on stage to aid the musician in hearing the whole band; often shaped like a cheese or pie wedge.
WEEE (Waste from Electrical and Electronic Equipment) European directive on disposal of electrical and electronic equipment. See RoHS.
weighted average An average that takes into account the proportional relevance of each component, rather than treating each component equally. [IEEE Std 1680]
weighting filters Special filters
used in measuring loudness levels, and consequently carried over into audio
noise measurements of equipment. The filter design "weights" or gives more
attention to certain frequency bands than others. The goal is to obtain
measurements that correlate well with the subjective perception of noise.
(Technically termed psophometric [pronounced "so-fo-metric"] filters,
after the psophometer, a device used to measure noise in telephone
circuits, broadcast, and other audio communication equipment. A psophometer
was a voltmeter with a set of weighting filters.) Weighting filters are
a special type of band-limiting
filters designed to compliment the way we hear. Since the ear's loudness
vs. frequency response is not flat, it is argued, we should not try to
correlate flat frequency vs. loudness measurements with what we hear. Fair
enough. Five weighting filter designs dominate (See: References: Metzler):
Editorial Note: Low-cost audio equipment often list an A-weighted noise spec — not because it correlates well with our hearing -- but because it helps "hide" nasty low-frequency hum components that make for bad noise specs. Sometimes A-weighting can "improve" a noise spec by 10 dB. Words to the wise: always wonder what a manufacturer is hiding when they use A-weighting. "However, an exception has arisen: Digital products using A/D and D/A converters regularly spec S/N and dynamic range using A-weighting. This follows the semiconductor industry's practice of spec'ing delta-sigma data converters A-weighted. They do this because they use clever noise shaping tricks to create 24-bit converters with acceptable noise behavior. All these tricks squeeze the noise out of the audio bandwidth and push it up into the higher inaudible frequencies. The noise may be inaudible, but it is still measurable and can give misleading results unless limited. When used this way, the A-weighting filter rolls off the high frequency noise better than the flat 22 kHz filter and compares better with the listening experience. The fact that the low-end also rolls off is irrelevant in this application." From RaneNote 145, Audio Specifications
Wendel The name given by Steely Dan's famous recording engineer, Roger Nichols, for the sampling sequencer that he built in 1978 for their hit song, "Hey Nineteen."
Wente, Edward Christopher (1889-19??) American engineer who invented the first condenser microphone in 1916 while working for Western Electric.
wet Recording. 1. The result of mixing the original recorded sound with the processed sound (reverb, chorusing, doubling, etc.). 2. Any sound with significant reverberation; not dead. Contrast with dry.
wet circuit See below.
wetting Electronics. 1. The free flow of solder alloy, with proper application of heat and flux, on a metallic surface to produce an adherent bond. [IEEE] 2. Wetted relay contacts prevent damaging chemicals such as oxides and hydrocarbons from forming on the contacts. The build-up increases the contact resistance which can cause a voltage drop and/or heating of the contacts. 2. The practice of wetting reed relay contacts with mercury; called mercury-wetted relay.
wet transformer Telephony. An analog audio transformer designed for both DC and AC operation. Derived from the term, wet circuit, referring to a circuit where voice signals are transmitted and also carries direct current. Contrast with dry transformer.
WFAE (World Forum for Acoustic Ecology) "An interdisciplinary spectrum of individuals engaged in the study of the scientific, social, and cultural aspects of natural and human made sound environments."
WFS (wave field synthesis) See wave field synthesis.
WFX Worship facilities conference & expo that brings together three church groups: Church Leaders, Technology Gurus, and Facilities Managers and teams.
whammy bar Electric Guitar. Nickname for the metal handle contraption found on some electric guitars that allows the player to momentarily change the tension (or actually stretch) the strings in order to create a vibrato effect (often mistakenly called a tremolo device).
Wheatstone bridge An instrument used for measuring resistance. The circuit used is a 4-arm bridge, all arms of which are predominantly resistive. The bridge is a two-port network (i.e., it has two terminal pairs across opposite corners) capable of being operated in such a manner that when voltage is applied to one port, by suitable adjustment of the resistive elements in the network, zero output can be obtained at the signal output port (usually a meter). Under these circumstances the bridges is termed balanced. [Although the circuit used in a Wheatstone bridge was first described by Samuel Hunter Christie (1784-1865) — the son of James Christie, founder of the well-known auction house — in his paper "Experimental Determination of the Laws of Magneto-electric Induction" (1833), Sir Charles Wheatstone (1802-1875) received credit for its invention because of his adaptation of the circuit in 1843 for the measurement of resistance. Wheatstone also invented the concertina, the stereoscope and contributed significantly to the development of the telegraph.]
windowing Signal Processing. The technique of analyzing small subsets of the total data.
whinny To neigh, as a horse, especially in a gentle tone. [AHD]
whippin' that ivory Playing the piano. [Decharne]
whispering gallery Acoustics. A space constructed of two parabolic dishes that focus sound to distinct spots. One famous example is the Mapparium in Boston.
whistle or whine Acoustics. Terms for noise in the 500 Hz to 2 kHz range. [Things like air conditioners and diffusers.] Musical Instrument. An end blown flute with a fipple.
white label Music. New twelve-inch vinyl singles with plain white labels used by record companies and DJs for their advance promotional copies.
Whitelabel.net Music. Free promotional download site for DJs and record labels for use with Rane/Serato Scratch Live systems.
white noise 1. Physics. Analogous to white light containing equal amounts of all visible frequencies, white noise contains equal amounts of all audible frequencies (technically the bandwidth of noise is infinite, but for audio purposes it is limited to just the audio frequencies). From an energy standpoint white noise has constant power per hertz (also referred to as unit bandwidth), i.e., at every frequency there is the same amount of power (while pink noise, for instance, has constant power per octave band of frequency). A plot of white noise power vs. frequency is flat if the measuring device uses the same width filter for all measurements. This is known as a fixed bandwidth filter. For instance, a fixed bandwidth of 5 Hz is common, i.e., the test equipment measures the amplitude at each frequency using a filter that is 5 Hz wide. It is 5 Hz wide when measuring 50 Hz or 2 kHz or 9.4 kHz, etc. A plot of white noise power vs. frequency change is not flat if the measuring device uses a variable width filter. This is known as a fixed percentage bandwidth filter. A common example of which is 1/3-octave wide, which equals a bandwidth of 23%. This means that for every frequency measured the bandwidth of the measuring filter changes to 23% of that new center frequency. For example the measuring bandwidth at 100 Hz is 23 Hz wide, then changes to 230 Hz wide when measuring 1 kHz, and so on. Therefore the plot of noise power vs. frequency is not flat, but shows a 3 dB rise in amplitude per octave of frequency change. Due to this rising frequency characteristic, white noise sounds very bright and lacking in low frequencies. [Here's the technical details: noise power is actually its power density spectrum - a measure of how the noise power contributed by individual frequency components is distributed over the frequency spectrum. It should be measured in watts/Hz; however it isn't. The accepted practice in noise theory is to use amplitude-squared as the unit of power (purists justify this by assuming a one-ohm resistor load). For electrical signals this gives units of volts-squared/Hz, or more commonly expressed as volts/root-Hertz. Note that the denominator gets bigger by the square root of the increase in frequency. Therefore, for an octave increase (doubling) of frequency, the denominator increases by the square root of two, which equals 1.414, or 3 dB. In order for the energy to remain constant (as it must if it is to remain white noise) there has to be an offsetting increase in amplitude (the numerator term) of 3 dB to exactly cancel the 3 dB increase in the denominator term. Thus the upward 3 dB/octave sloping characteristic of white noise amplitude when measured in constant percentage increments like 1/3-octave.] See noise color. 2. Music. Slang term for music that is discordant with no melody; disagreeable, harsh or dissonant.
white space Communication. Term for the theoretically unused frequency spectrum separating analog TV channels. While unused in theory, it is in fact where pro audio wireless microphones and monitors operate.
Whodini Early NY-based hip-hop group, contemporaries of Grandmaster Flash and the Furious Five and Afrika Bambaataa.
whole tone or whole step Music. Two notes spaced 1/6 octave apart. Contrast with semitone.
Wicks, Charlie (1945-2010) American entrepreneur best remembered as the founder of Pro Co Sound company and his self-proclaimed title: Captain of the Universe.
wide-range curve Same as X curve.
widget (perhaps alteration of gadget) 1. A small mechanical device or control; a gadget. 2. An unnamed or hypothetical manufactured article. [AHD] 3. As developed by Guinness, a small disk with a pinprick-size hole that fits inside their beer cans. As the beer is packaged, a small amount of stout is forced into the widget and held there under pressure. Once the pressure is released by opening the can, the beer is freed from the widget and a stream of bubbles flows upward. Now when the stout is poured, it looks like a pub-poured draught with the characteristic Guinness head (thick collar of foam), without the widget it looks like any other beer. It also reproduces the creamy texture and low carbonation of a draught pint. Now also used by Murphy's and Beamish.
Widlar, Bob (1937-1991) Famous eccentric American pioneer linear IC designer who created the first op amp ICs, among many other IC innovations.
widow's piano Inferior instruments sold as bargains. [Kacirk]
Wi-Fi (wireless fidelity) Shorten form for the Wi-Fi Alliance, a nonprofit international association formed in 1999 to certify interoperability of wireless Local Area Network products based on IEEE 802.11 specification. Wi-Fi Certification results from testing 802.11-based wireless equipment to make sure it meets the Wi-Fi standard and works with all other manufacturers' Wi-Fi equipment on the market. See the RaneNote Wireless Control of RPM Series Drag Net Programmable Processors.
wiki wiki Hawaiian word meaning "quick" used to create the name of Wikipedia, the free encyclopedia — a fantastic resource.
Wild Life Festival A four-stage, two-day music festival held at the Brighton City Airport, U.K.
wild sound Film & Video Sound. Audio recorded independent of the visual it may accompany.
Williams, Jim See: Jim Williams.
Williwaw Name for howling ferocious cold winds common to Alaska and the Straits of Magellan.
WiMN (Women in Music Network) "A hub for all women’s groups and organizations within the music and audio industries to share information, news, and events to a broader community of female industry professionals and performers." [from website] Not to be confused with Women in Media and News, a different WiMN.
wind profiler See sodar.
windscreen Microphones. A porous covering for a microphone, designed to reduce the electrical signal produced by the microphone as a result of noise generated by the passage of wind over the microphone. [Harris]
windshield Microphones. Slang for a pop filter or windscreen.
Wintel A contraction of the words "Windows" and "Intel." Used to describe personal computers made from Intel microprocessors and running Microsoft Windows software. It is reported that this "Wintel standard" accounts for 80% of all PCs.
Wintergatan Marble Machine See: marvelous marble machine.
WIPO (World Intellectual Property Organization) "An international organization dedicated to helping to ensure that the rights of creators and owners of intellectual property are protected worldwide and that inventors and authors are, thus, recognized and rewarded for their ingenuity."
wire See cables.
wireway Sheet-metal troughs with hinged or removable covers to house and protect wires and cables external to panelboards and cabinets. [IEEE]
wiring classes U.S. National Electrical
Code (NEC) defines three classes of wiring according to their fire
and shock hazard potential:
wire gauge vs. resistance See chart and info AWG.
WLAN (wireless local area network) See Wi-Fi for example.
WMC (Winter Music Conference) " ... regarded as the singular networking event in the dance music industry, attracting professionals from over 70 different countries."
wobble board Musical Instrument. Australian instrument invented by Rolf Harris. The board is flexed in and out to create a "whoop-whoop" sound.
WOM (write-only-memory) Term coined by Signetics in 1972 for their 25000 Series 9046XN Random Access Write-Only-Memory integrated circuits. Based on SEX (Signetics EXtra secret) processes, these devices employ both enhancement and depletion mode P-Channel, N-Channel, and NEU-Channel MOS transistors (devices which simultaneously, randomly, or not at all, enhance or deplete regardless of gate polarity). The world's supply of WOMs was quickly consumed by newly designed airline baggage-handling equipment, where they are still used today to store the exact real-time location of each bag. WOM production was suddenly discontinued when it was discovered that the only copy of the mask code had been accidentally filed into a WOM location. See: Best of Bob Pease.
WOMAD (World of Music, Art & Dance) First created in 1981 by Thomas Brooman along with Peter Gabriel, the first festival was called the International Music and Arts, then renamed WOMAD for the second festival in 1982.
Wonder, Stevie Stage name of Steveland Judkins.
wood block (also woodblock) Musical Instrument. A two-toned percussion instrument made from a single piece of wood with one or two longitudinal cavities.
woodpile Hipster slang for a xylophone. [Decharne]
woofer Low-frequency loudspeaker. See crossover.
word An ordered set of bits that is the normal unit in which information may be stored, transmitted, or operated upon within a given computer — commonly 16 or 32 bits.
word clock The synchronizing signal that indicates the sampling frequency or rate of sample words over a digital audio interface.
word length The number of bits in a word.
word-pecker One that plays with words. [Kacirk]
work Physics. The scalar product of the force on a body and the displacement of the body. In simpler terms, it is force on a body times the distance the body moves in the direction of the force. The symbol for work is W and its SI unit is the joule (J). [ IEEE Std 270]
working voltage to ground Electric Instruments. The highest voltage, in terms of maximum peak value, that should exist between any terminal of the instrument proper on the panel, or other mounting surface, and ground. [IEEE]
worldizing Film & Video Sound. This refers to playing back existing recordings through a speaker or speakers in real-world acoustic situations, and recording that playback with microphones so that the new recording takes on the acoustic characteristics of the place it was "re-recorded." [From the link.] Term coined by Walter Murch, famous film editor and sound engineer.
World Music Day See: Fête de la Musique.
World Wide Web (WWW and/or W3) 1. A way to present resources and information over the Internet, or according to its inventor, British scientist Tim Berners-Lee, while at CERN in 1989, "The World Wide Web (W3) is the universe of network-accessible information, an embodiment of human knowledge." 2. Satirically called the World Wide Wait.
WORM or WOROM (write-once read-only memory) Systems in which data may be written once, but not erased and rewritten. Usually refers to CD-ROM technology that can be recorded once only.
wow A form of distortion due to very slow (~ 1 Hz) variations in rotational speed common to turntables and analog tape recorders. Heard as a slow variation in the pitch when played back. Compare with flutter.
WPAN (wireless personal-area network) For instance, see Bluetooth and ZigBee.
Wray, Link (1929-2006) American musician most famous for his 1958 hit "Rumble."
write To record data on a medium.
wuankara Musical Instrument. Chinese bamboo pipe.
WWW (World Wide Web) See World Wide Web.
wye connector See Y-connector.
wye-delta transformation Electronic Circuit Analysis. A very useful mathematical technique for simplifying the analysis of certain electrical networks shaped like the letter Y.
WYSIWYG (pronounced "whizzy-wig") (what you see is what you get) Popular word processing term. Folklore says it was copied from a catchphrase from the old TV show Rowan and Martin's Laugh-In.