Pro Audio Reference


Pro Audio Reference (X)


x The mathematical symbol for abscissa, the coordinate representing the position of a point along a line perpendicular to the y-axis in a plane Cartesian coordinate system.

x The mathematical symbol for "times."

X The electronic symbol for reactance — the imaginary part of impedance.

XC The electronic symbol for capacitive reactance.

XL The electronic symbol for inductive reactance.

xACT ( x audio compression toolkit ) An audio compression GUI app for Mac developers. [Not XACT below.]

XACT (cross-platform audio creation tool) A Microsoft digital audio development tool. Hit the link for details. [Not xACT above.]

X-ACTO Hand-tools. The best known hand-tool manufacturer in the world founded by Sundel Doniger in New York City in 1917.

xalam Musical Instrument. A West African stringed musical instrument.

xanthous 1. Yellow. 2. Having light brown or yellowish skin. [AHD]

Xaudio™ Trademark of Intertrust® for their proprietary multi-platform MPEG audio solution for digital playback development.

x-axis The horizontal axis of a two-dimensional Cartesian coordinate system, or one of three axes in a three-dimensional Cartesian coordinate system. [AHD]

x-band Broadcast. A radar-frequency band between 8 GHz and 12 GHz, usually in the ITU assigned band 8.5 GHz to 10.68 GHz. [IEEE]

XBASEY Networks. Nomenclature designation for IEEE 802.3 or Ethernet cabling. The "X" is the data rate and the "Y" is the cabling type or category. See Ethernet.

XBT (expendable bathythermograph) Acoustics. Abbreviation found in underwater acoustics studies. See bathythermograph.

x-copy A copy made as closely as possible to a 1:1 match. In analog this applies to "equal flux" copying, wherein a copy is made at the same flux levels as the master. [Holman]

X curve (extended curve) In the film sound industry an X curve is also known as the wide-range curve and conforms to ISO Bulletin 2969, which specifies for pink noise, at the listening position in a dubbing situation or two-thirds of the way back in a theater, to be flat to 2 kHz, rolling off 3-dB/oct after that. The small-room X curve is designed to be used in rooms with less than 150 cubic meters, or 5,300 cubic feet. This standard specifies flat response to 2 kHz, and then rolling off at a 1.5 dB/oct rate. Some people use a modified small-room curve, starting the roll-off at 4 kHz, with a 3 dB/oct rate. Compare with Academy curve.

x-cut Oscillators. A method of cutting a quartz plate for an oscillator, with the x-axis of the crystal perpendicular to the faces of the plate. Contrast with y-cut.

xdcr Electronics. Abbreviation for transducer.

xDSL Telecommunications. (X-type) Digital Subscriber Line.

Xe Chemistry. The symbol for the element xenon.

Xenakis, Iannis Greek composer who used flicker noise to randomly generate compositions he called stochastic music.

xenoglossy The (alleged) faculty of speaking a language one has not learned. [OED]

xenon Chemistry. The gas found inside vacuum tubes.

Xenu Link Sleuth Computer Software. A program used to check for broken hyperlinks.

xerography The name created by the Haloid Company in 1946 (from the Greek xeros for dry and graphein for writing) for the process invented by Chester F. Carlson on October 22, 1938, which he named electrophotography. In 1960, Haloid-Xerox introduced the 914 copier, the first pushbutton, plain-paper, xerographic office machine. The company soon became known simply as Xerox.

xerothermic 1. Both dry and hot: a xerothermic climate. 2. Adapted to or flourishing in an environment that is both dry and hot: xerothermic organisms. [AHD]

Xerox See: xerography.

x-fader DJ Mixers. Shortened form for crossfader.

xfmr Electronics. Abbreviation for transformer.

X Generation See Generation X.


XGMII 10 Gb media independent interface [IEEE Std 802.17]


XHTML Internet. Extensible HTML. Hit the XHTML link for all the nitty gritty.

Xi The 14th letter of the Greek alphabet.

Xiao Musical Instrument. An ancient Chinese flute.

Xilinx®(pronounced zi-links; after xi the 14th letter of the Greek alphabet) Leading manufacturer of field-programmable logic devices.

xingxong (sing-song) "A term used to describe a song which is overplayed." —

Xirula Musical Instrument. Small three hole flute from the Basque region.

XLD See connectors.

xlnt Shorthand for "excellent."

XLR See connectors.

XM Satellite radio station; now merged with Sirius.

Xmas Abbreviation for Christmas. (From X, the Greek letter chi, first letter of Greek Khristos, meaning Christ.) [Usage Note: Xmas has been used for hundreds of years in religious writing, where the X represents a Greek chi, the first letter of Χριστος, "Christ." In this use it is parallel to other forms like Xtian, "Christian." But people unaware of the Greek origin of this X often mistakenly interpret Xmas as an informal shortening pronounced (eks?m?s). Many therefore frown upon the term Xmas because it seems to them a commercial convenience that omits Christ from Christmas.]

Xmax Loudspeakers. Mathematical symbol for the maximum liner excursion of a driver cone; measured in millimeters.

XMF (extensible music format) A MIDI Manufacturers Association approved new standard that combines MIDI notes with DLS (downloadable sound) samples.

xmit Electronics. Abbreviation for transmit.

XML A metalanguage written in SGML that allows one to design a markup language, used to allow for the easy interchange of documents on the World Wide Web. [AHD]

XMSN Official (FED-STD-1037C) abbreviation for transmission.

XMTD Official (FED-STD-1037C) abbreviation for transmitted.

XMTR Electronics. Official (FED-STD-1037C) abbreviation for transmitter.

XNOR Acronym for exclusive NOR, a type of logic gate where a logic 1 output is based upon either both A or B inputs being present or not present, but not one without the other.

xo Official (FED-STD-1037C) abbreviation for crystal oscillator.

Xophonic Signal Processing. "An artificial reverberation device for the home made by Radio Craftsmen in the 1950s. The Xophonic was a box that looked about like a bookshelf loudspeaker [Hit the link to see a photo]. It contained an analog time delay device in the form of a small loudspeaker connected to a coil of tubing about 50 feet long with a microphone in the other end, producing a time delay of about 50 milliseconds. The incoming signal from the amplifier of the sound system was fed to the time delay unit and to a mixer, which combined it with the delayed signal from the tube microphone. A power amplifier and loudspeaker were included to amplify and radiate this combined signal into the listening room.

The Xophonic was probably the first signal processing device intended for home use. It enjoyed a brief popularity, and then quietly fell into oblivion, aided by the advent of the stereophonic record." [White] The concept was resurrected by UREI in the '70s as the Cooper Time Cube.

XOR Acronym for exclusive OR, a type of logic gate where a logic 1 output is based upon A or B inputs being present - but not both.

xote Dance. A Brazilian music and dance genre.

xovr Abbreviation for crossover.

xoxozzz Shorthand for hugs and kisses and sweet dreams.

XP (Extreme Programming) A popular software development system created by Kent Beck.

x-percentile-exceeded sound level Acoustics. The fast A-weighted sound level equaled or exceeded by a fluctuating sound level x percent of a stated time period. For example, the letter symbol L10 represents that sound level which is exceeded 10 percent of the stated time period. [Harris]

X/R ratio Electronics. The ratio of reactance to resistance. It indicative of the rate of decay of any dc offset. A large X/R ratio corresponds to a large time constant and a slow rate of decay. [IEEE]

x-ray A relatively high-energy photon having a wavelength in the approximate range from 0.01 to 10 nanometers. [AHD]

X-SAMPA (Extended SAM Phonetic Alphabet) Phonetics. A variant of SAMPA that extends it to cover all characters in the IPA.

xstr Electronics. Abbreviation for transistor.

XSV Underwater Acoustics. Abbreviation for expendable sound velocimeter.

XT Official (FED-STD-1037C) abbreviation for crosstalk.

xtal Official (FED-STD-1037C) abbreviation for crystal.

xun Musical Instrument. A Chinese vessel flute.

x-wave Acoustics. A type of localized wave that propagates as an axisymmetric pulse, with a wavefront cross-section (in a plane through the beam axis) that resembles the letter X. Because of their ability to remain focused while propagating over distances comparable with the Rayleigh distance, such waves have acoustical applications in nondestructive testing and medical imaging. [Morfey]

X-Y display A rectangular coordinate plot of two variables. [IEEE]

xylophone Musical Instrument. A percussion instrument consisting of a mounted row of wooden bars graduated in length to sound a chromatic scale, played with two small mallets. Word History: Alphabet books for children frequently feature the word xylophone because it is one of the few words beginning with x that a child (or most adults, for that matter) would know. The majority of English words beginning with x, including many obscure scientific terms, are of Greek origin, the x, pronounced (z), representing the Greek letter xi. In the case of xylophone, xylo- is a form meaning "wood," derived from Greek xulon, "wood," and -phone represents Greek phn, "voice, sound," the same element found in words such as telephone, microphone, and megaphone. This famous x-word is first recorded in the April 7, 1866, edition of the Athenaeum: "A prodigy ... who does wonderful things with little drumsticks on a machine of wooden keys, called the 'xylophone.'" [AHD] See woodpile

xylorimba (xylophone + marimba) Musical Instrument. A xylophone with an extended range to include that of the marimba.

X-Y microphone technique A stereo recording technique where two cardioid microphones are placed facing each other, at an angle of 90 degrees, with the center of the source aimed at the center between them. Sometimes this technique is incorporated internally in a single microphone using two capsules. Also called the coincident-microphone technique and intensity stereo Compare with ORTF

Xyndas, Spyridon (1812-1896) Greek composer.

X-Y recorder An output device that sketches the relationship between two variables onto a grid of plane rectangular coordinates. [AHD]

X-Y switch Electronics. A remotely controlled bank-and-wipe switch arranged in a flat manner, in which the wipers are moved in a horizontal plane, first in one direction and then in another. [IEEE]

xyz - "Examine your zipper." Example: "When seeing someone in class or at work with their zipper down, you can discreetly say, 'XYZ'" —

AES - Audio Engineering Society