Lights flash at frequency f = 0.5 Hz (Hz = hertz), 1.0 Hz and 2.0 Hz, where Failed to parse (Missing texvc executable; please see math/README to configure.): x

Hz means Failed to parse (Missing texvc executable; please see math/README to configure.): x
flashes per second. T is the period and T = Failed to parse (Missing texvc executable; please see math/README to configure.): y
s (s = second) means that Failed to parse (Missing texvc executable; please see math/README to configure.): y

is the number of seconds per flash. T and f are each other's reciprocal: f = 1/T and T = 1/f.

The hertz (symbol Hz) is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon.^[1] One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications. The word "hertz" is named for Heinrich Rudolf Hertz, who was the first to conclusively prove the existence of electromagnetic waves.

Definition[link]

The hertz is equivalent to cycles per second.^[2] In defining the second, the CIPM declared that "the standard to be employed is the transition between the hyperfine levels F = 4, M =  0 and F = 3, M = 0 of the ground state 2S_1/2 of the cesium 133 atom, unperturbed by external fields, and that the frequency of this transition is assigned the value 9 192 631 770 hertz"^[3] thereby effectively defining the hertz and the second simultaneously.

In English, hertz is used as a plural.^[4] As an SI unit, Hz can be prefixed; commonly used multiples are kHz (kilohertz, 10³ Hz), MHz (megahertz, 10⁶ Hz), GHz (gigahertz, 10⁹ Hz) and THz (terahertz, 10¹² Hz). One hertz simply means "one cycle per second" (typically that which is being counted is a complete cycle); 100 Hz means "one hundred cycles per second", and so on. The unit may be applied to any periodic event—for example, a clock might be said to tick at 1 Hz, or a human heart might be said to beat at 1.2 Hz. The "frequency" (activity) of aperiodic or stochastic events, such as radioactive decay, is expressed in becquerels.

Even though angular velocity, angular frequency and hertz all have the dimensions of 1/s, angular velocity and angular frequency are not expressed in hertz,^[5] but rather in an appropriate angular unit such as radians per second. Thus a disc rotating at 60 revolutions per minute (rpm) is said to be rotating at either 2π rad/s or 1 Hz, where the former measures the angular velocity and the latter reflects the number of complete revolutions per second. The conversion between a frequency f measured in hertz and an angular velocity ω measured in radians per second are:

Failed to parse (Missing texvc executable; please see math/README to configure.): \omega = 2\pi f \,

and Failed to parse (Missing texvc executable; please see math/README to configure.): f = \frac{\omega}{2\pi} \, 

. This SI unit is named after Heinrich Hertz. As with every International System of Units (SI) unit whose name is derived from the proper name of a person, the first letter of its symbol is upper case (Hz). When an SI unit is spelled out in English, it should always begin with a lower case letter (hertz), except where any word would be capitalized, such as at the beginning of a sentence or in capitalized material such as a title. Note that "degree Celsius" conforms to this rule because the "d" is lowercase. —Based on The International System of Units, section 5.2.

History[link]

The hertz is named after the German physicist Heinrich Hertz who made important scientific contributions to the study of electromagnetism. The name was established by the International Electrotechnical Commission (IEC) in 1930.^[6] It was adopted by the General Conference on Weights and Measures (CGPM) (Conférence générale des poids et mesures) in 1960, replacing the previous name for the unit, cycles per second (cps), along with its related multiples, primarily kilocycles per second (kc/s) and megacycles per second (Mc/s), and occasionally kilomegacycles per second (kMc/s). The term cycles per second was largely replaced by hertz by the 1970s.

The term "gigahertz", most commonly used in computer processor clock rates and radio frequency (RF) applications, can be pronounced either /ˈɡɪɡəhɜrts/, with a hard /ɡ/ sound, or /ˈdʒɪɡəhɜrts/, with a soft /dʒ/^[7] (see giga-#Pronunciation). The prefix "giga-" is derived directly from the Greek "γιγας" ("giant").

Applications[link]

Sine waves of different frequency.

Details of a heartbeat as an example of a non-sinusoidal periodic phenomenon that can be described in terms of hertz. Two complete cycles are illustrated.

Vibration[link]

Sound is a traveling wave which is an oscillation of pressure. Humans perceive frequency of sound waves as pitch. Each musical note corresponds to a particular frequency which can be measured in hertz. An infant's ear is able to perceive frequencies ranging from 20 Hz to 20,000 Hz; the average adult human can hear sounds between 20 Hz and 16,000 Hz.^[8] The range of ultrasound, high-intensity infrasound and other physical vibrations such as molecular vibrations extends into the megahertz range and well beyond.

Electromagnetic radiation[link]

Electromagnetic radiation is often described by its frequency—the number of oscillations of the perpendicular electric and magnetic fields per second—expressed in hertz.

Radio frequency radiation is usually measured in kilohertz (kHz), megahertz (MHz), or gigahertz (GHz). Light is electromagnetic radiation that is even higher in frequency, and has frequencies in the range of tens (infrared) to thousands (ultraviolet) of terahertz. Electromagnetic radiation with frequencies in the low terahertz range, (intermediate between those of the highest normally usable radio frequencies and long-wave infrared light), is often called terahertz radiation. Even higher frequencies exist, such as that of gamma rays, which can be measured in exahertz. (For historical reasons, the frequencies of light and higher frequency electromagnetic radiation are more commonly specified in terms of their wavelengths or photon energies: for a more detailed treatment of this and the above frequency ranges, see electromagnetic spectrum.)

Computing[link]

In computing, most central processing units (CPU) are labeled in terms of their clock rate expressed in megahertz or gigahertz (10⁶ or 10⁹ hertz, respectively). This number refers to the frequency of the CPU's master clock signal ("clock rate"). This signal is simply an electrical voltage which changes from low to high and back again at regular intervals. This signal is a square wave. Hertz has become the primary unit of measurement accepted by the general populace to determine the performance of a CPU, but many experts have criticized this approach, which they claim is an easily manipulable benchmark.^[9] For home-based personal computers, the CPU has ranged from approximately 1 megahertz in the late 1970s (Atari, Commodore, Apple computers) to up to 6 GHz in the present (IBM POWER processors) and up to 8 GHz overclocked (AMD FX processors).^[10]

Various computer buses, such as the front-side bus connecting the CPU and northbridge, also operate at different frequencies in the megahertz range

[edit] SI multiples

Frequencies not expressed in hertz[link]

Even higher frequencies are believed to occur naturally, in the frequencies of the quantum-mechanical wave functions of high-energy (or, equivalently, massive) particles, although these are not directly observable, and must be inferred from their interactions with other phenomena. For practical reasons, these are typically not expressed in hertz, but in terms of the equivalent quantum energy, which is proportional to the frequency by the factor of Planck's constant.

See also[link]

References[link]

External links[link]

• BIPM Cesium ion f_Cs definition
• National Research Council of Canada: Generation of the Hz
• National Research Council of Canada: Cesium fountain clock
• National Physical Laboratory: Trapped ion optical frequency standards
• National Research Council of Canada: Optical frequency standard based on a single trapped ion
• National Research Council of Canada: Optical frequency comb
• One Hertz in Radians per Second (Google). Note, as of 06 May 2009 there is an error of 2Failed to parse (Missing texvc executable; please see math/README to configure.): \pi

.

v t e SI units Base units Ampere · Candela · Kelvin · Kilogram · Metre · Mole · Second Derived units Becquerel · Coulomb · Degree Celsius · Farad · Gray · Henry · Hertz · Joule · Katal · Lumen · Lux · Newton · Ohm · Pascal · Radian · Siemens · Sievert · Steradian · Tesla · Volt · Watt · Weber Accepted for use with SI Dalton (Atomic mass unit) · Astronomical unit · Day · Decibel · Degree Celsius · Degree of arc · Electronvolt · Hectare · Hour · Litre · Minute · Minute of arc · Neper · Second of arc · Tonne Atomic units · Natural units See also SI prefixes · Systems of measurement · Conversion of units · New SI definitions · History of the metric system Book:International System of Units  · Category:SI base units

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The Crystal Method
The Crystal Method performing at SXSW 2009.
Background information
Origin	Los Angeles, California, United States
Genres	Alternative dance, chemical breaks, big beat, breakbeat, EDM
Years active	1993–present
Labels	Outpost, Geffen, V2, Tiny E
Website	TheCrystalMethod.com
Members
Scott Heisler Kirkland Ken B. Jordan

The Crystal Method is an American electronic music duo that was created in Las Vegas, Nevada by Ken Jordan and Scott Kirkland in the early 1990s. The Crystal Method's music has appeared in numerous TV shows, films, video games, and advertisements. Their best-selling album, Vegas, was certified platinum in 2007.

Biography[link]

The Crystal Method is made up of two members, Ken Jordan and Scott Kirkland. Before The Crystal Method was formed, Ken and Scott started working on music while working at the grocery store and while Ken was a local DJ in Las Vegas as well as the college radio program director at UNLV. Ken taught Scott how to DJ, and when Ken moved to L.A. to work for a producer, Scott took over his job DJ'ing at the local club. Scott would follow Ken out to L.A., and they formed The Crystal Method in 1993.

Early days (1993–1995)[link]

By the early '90s, both Ken and Scott had moved from Las Vegas to Los Angeles. Ken Jordan and Scott Kirkland bought a house together, in Glendale, California, which had a small underground shelter beneath the front lawn. Originally intending to turn the shelter into a studio, it proved to be an unrealistic idea and the duo set up a studio in their house (which was located under a Los Angeles Overpass. They subsequently named their studio The Bomb Shelter.The Crystal Method (interview) (1999). Better Living Through Circuitry (Motion picture). United States: Cleopatra Pictures. http://us.imdb.com/title/tt0207998/. 

After The Bomb Shelter was built, a tape of The Crystal Method's music found its way to a British DJ named Justin King. King was interested in starting a record label that would showcase American electronic dance acts. King teamed up with Scottish Steve Melrose to form the record label City of Angels. The first official release from the City of Angels label was The Crystal Method's "Now is the Time". The Crystal Method were signed to Outpost Recordings in 1996.

[edit] Vegas (1996–1998)

After the band signed with Outpost, they began working on their debut album. The group's second (and last) single on City of Angels was "Keep Hope Alive". Their next release was on the Mortal Kombat: More Kombat soundtrack, "Come2gether".

On September 8, 1997, The Crystal Method released their best-selling album, Vegas. Vegas peaked at number 92 on the Billboard 200.^[1] It was certified gold by the RIAA in 1998, then platinum in 2007.^[2]

Five of the album's ten tracks were released as singles: "Trip Like I Do", "Busy Child", "High Roller", "Comin' Back", and "Keep Hope Alive".

[edit] Tweekend (1999–2002)

In 1999, the band went into the studio to record their next studio album, Tweekend, which featured more guest artists than Vegas had. The album was released in July 2001, and peaked at number 32 on the Billboard 200,^[1] which is still the group's highest album chart position.

Featured guests from the album include Rage Against the Machine guitarist Tom Morello, Stone Temple Pilots vocalist Scott Weiland, and others, like Doug Grean, DJ Swamp, Ryan "Ryu" Maginn, and Julie Gallios. Four singles were released from Tweekend: "Wild, Sweet and Cool", "Murder", "Blowout", "Name of the Game".

[edit] Community Service

Jordan and Kirkland used to have a radio show called "Community Service" which aired Friday nights on radio station Indie 103.1, in California.^{[citation needed]} They played electronic music and hosted guests, like Death in Vegas and UNKLE. Their show came back on air in 2011 and airs weekly on Sirius XMs Channel 52.

A year after the release of Tweekend, The Crystal Method released a continuous mix album based on their radio show, titled Community Service. The album does not feature any new studio material from The Crystal Method, but is composed of remixes of bands like P.O.D., Rage Against the Machine, and Garbage, plus remixes of songs from Tweekend. Their remix of P.O.D.'s "Boom" from this album, also appeared in the video game Amplitude.

Community Service peaked at number 160 on the Billboard 200, number five on the Top Electronic Albums chart, and number 15 on the Top Independent Albums chart.^[1]

[edit] Legion of Boom (2003–2005)

After the release of Community Service, The Crystal Method went back into the studio to record their third album, Legion of Boom. During the recording, they used the house as their recording studio instead of The Bomb Shelter.^{[citation needed]}

In December 2003, the single "Born Too Slow", with vocals from John Garcia and guitar by Wes Borland was released. Legion of Boom was released on January 13, 2004, and peaked at number 36 on the Billboard 200.^[1] It sold over 25,000 copies in its first week.^[3] The track was also part of the soundtrack of the very popular racing game Need for Speed: Underground, used prominently especially in its demo.

The other single released from Legion of Boom, "Starting Over", featured vocals from Rahzel from The Roots. No other singles were released but other songs, including "Weapons of Mass Distortion", "Bound Too Long" and "Realizer", appeared in various movies and TV shows. "I Know It's You" appeared in the trailer for the film Resident Evil: Extinction, and includes vocals by the movie's star, Milla Jovovich.

In 2005, the album was nominated for the Best Electronic/Dance Album Grammy,^[4] the first year that category existed. It lost to Kish Kash by Basement Jaxx.^[5]

It is also around this time that Jordan and Kirkland formed their own record label, called Tiny e Recordings.^[3]

[edit] Community Service II

On April 5, 2005, The Crystal Method released their sequel to Community Service, called Community Service II, another continuous mix of electronica songs and remixes of music by artists including The Doors, Unkle, New Order and Smashing Pumpkins. The album peaked at number 31 on the Top Independent Albums chart and number 8 on the Top Electronic albums chart.^[1]

A 5-track EP, Community Service II Exclusives, was also released through the iTunes Store. It included one new track, "Badass", and full versions of four tracks from Community Service II. It was removed from the iTunes store not long after it was released.^[3]

[edit] Drive, London, and Vegas re-release (2006–2008)

The group composed and performed the score for the film London, which was released in February 2006. The soundtrack album included excerpts from the score, two Crystal Method vocal tracks—"Smoked" and "Glass Breaker", which were also released as a single—and songs by artists like Evil Nine, The Out Crowd, and The Perishers.

Shortly after the release of the London soundtrack, The Crystal Method was approached by Nike to take part in a series of music releases specifically designed to be listened to while running. The group's contribution, Drive: Nike + Original Run—the first in the series^[6]—was initially released digitally, in June 2006, with the physical release following a year later. Drive peaked at number 23 on the Top Electronic Albums chart.^[1] The album, a 45 minute continuous mix, starts off slow, increases in tempo, and slows at the end, following the arc of a typical distance run.^[3] In 2006 the track Robogirl released by the duo appeared on Dance Dance Revolution: SuperNOVA as well. ^[7]

In 2007, ten years after its original release, the group's debut album, Vegas was certified platinum by the RIAA.^[2] One month later, a special edition of the album was released, with a second disc including remixes and video.

In late 2008, the group remixed their song "Now Is the Time". Where the original version featured samples of Jesse Jackson, this "Vote '08 Remix" used samples of Barack Obama, marking the presidential election.

[edit] Divided by Night (2009–present)

Following the release of Legion of Boom, The Crystal Method began construction of a new, full-sized recording studio in Los Angeles—Crystalwerks. When it was finished, they began work on their next album, Divided by Night.

On April 14, 2009, The Crystal Method released the digital single "Drown in the Now". A second single, "Black Rainbows", was released via Beatport two weeks later.

The Divided by Night tour started in Boston on May 6, and the album was released the following week. It peaked at number 38 on the Billboard 200, number two on the Top Electronic Albums chart, and number four on the Top Independent Albums chart,^[1] and also granted the duo another Grammy nomination. The album features guest artists including Peter Hook (of New Order), Matisyahu, Meiko, Justin Warfield, Emily Haines (of Metric), and Jason Lytle.

X Games 3D: The Movie, released in August 2009, included a number of Crystal Method songs and remixes,^[8] including "Drown in the Now" and "Now Is the Time".

"Re:Generation Music Project 2012"[link]

The Crystal Method's most recent track "I'm Not Leaving," featured a collaboration with Motown's Martha Reeves for the Re:Generation Music Project documentary. The film followed five DJ/producers who each collaborated with one of five singers, each from a different genre of music.

Instruments[link]

The Crystal Method use a wide array of equipment, with the Clavia Nord Lead being most closely associated with their style and sound. It was the primary source of sound for their first album Vegas.^{[citation needed]}

Discography[link]

• Vegas (1997)
• Tweekend (2001)
• Legion of Boom (2004)
• Divided by Night (2009)

References[link]

External links[link]

• Official website
• The Crystal Method at Allmusic
• The Crystal Method at the Internet Movie Database