Information about Sampling (music)

In music, sampling is the act of taking a portion, or sample, of one sound recording and reusing it as an instrument or element of a new recording. This is typically done with a sampler, which can be a piece of hardware or a computer program on a digital computer. Sampling is also possible with tape loops or with vinyl records on a phonograph.

Often "samples" consist of one part of a song, such as a break, used in another, for instance the use of the drum introduction from Led Zeppelin's "When the Levee Breaks" in songs by the Beastie Boys, Dr. Dre, Eminem, Mike Oldfield, Rob Dougan and Erasure, and the guitar riffs from Foreigner's "Hot Blooded" in Tone-Loc's "Funky Cold Medina". "Samples" in this sense occur often in Industrial music, often using spoken words from movies and TV shows, as well as electronic music (which developed out of the musique concrète style, based almost entirely on samples and sample-like parts), hip hop, developed from DJs repeating the breaks from songs (Schloss 2004, p.36), and Contemporary R&B, but are becoming more common in other music as well, such as by Slipknot's sample player Craig Jones.

In 2005, music blog Library of Vinyl Experience compiled sample frequency data obtained from the sample database The Sample FAQ. The goal was to determine what year was “The Funkiest Year Ever” by counting the number of times samples from a particular year were used in hip hop songs. The bulk of the samples used in hip hop were from the years 1970-1975, the most being 872 different songs from 1973, making it “The Funkiest Year Ever”. Some of 1973s most sampled songs include; The Incredible Bongo Band’s “Apache”, which was sampled 45 times, Barry White’s “I’m Gonna Love You Just a Little More, Babe”, which was sampled 33 times, Kool and the Gang’s “Jungle Boogie”, which was sampled 45 times, and The Honeydrippers’ “Impeach the President”, which was sampled 115 times.^[1]

Samplers

Main article: Sampler (musical instrument)

Legal issues

Sampling has been an area of contention from a legal perspective. Early sampling artists simply used portions of other artists' recordings, without permission; once rap and other music incorporating samples began to make significant money the original artists began to take legal action, claiming copyright infringement. Some sampling artists fought back, claiming their samples were fair use (a legal doctrine in the USA that is not universal).

Early cases

Though sampling existing (copyrighted) recordings using manipulation with tape recorders goes back at least as far as 1961, when James Tenney created Collage #1 ("Blue Suede") from samples of Elvis Presley's recording of the song "Blue Suede Shoes" sampling did not take off in popular music until the early eighties when pioneering hip hop producers, such as Marley Marl, started to produce Rap records using sampled breaks rather than drum machines or live studio bands, which had until then been the norm. The first rap single to feature sampling was "Rapper's Delight" by Sugar Hill Gang on their own independent Sugar Hill Label in 1979. They used the guitar riff from the song "Good Times" by the disco group Chic.

Early examples of this practice include the West Street Mob's - Break Dance (Electric Boogie) (1983) (which used the "Apache" break by the Incredible Bongo Bong Band), Brother D and the Collective Effort's "How We Gonna Make The Black Nation Rise" (1984) (which sampled the beat and bass line from Cheryl Lynn's 1981 hit "Got to be Real") and UTFO's "Roxanne Roxanne" (1984). Bill Holt's Dreamies (1974)is often cited as one of the earliest examples of sampling in popular music. Another early example of sampling was Big Audio Dynamite and their 1985 album This Is Big Audio Dynamite and the single E=MC² which Mick Jones (the bands main creative force, formerly of The Clash) sampled snippets of audio from various films including works by Nicolas Roeg which make up the Roeg homage E=MC².

One of the first major legal cases regarding sampling was with UK dance act M/A/R/R/S "Pump Up the Volume". As the record reached the UK top ten, producers Stock Aitken Waterman obtained an injunction against the record due to the unauthorized use of a sample from their hit single "Roadblock". The dispute was settled out of court, with the injunction being lifted in return for an undertaking that overseas releases would not contain the "Roadblock" sample, and the disc went on to top the UK singles chart. Ironically, the sample in question had been so distorted as to be virtually unrecognizable, and SAW didn't realize their record had been used until they heard co-producer Dave Dorrell mention it in a radio interview.

2 Live Crew, a hip-hop group not unfamiliar with controversy, was often in the spotlight for their ‘obscene’ and sexually explicit lyrics. They sparked many debates about censorship in the music industry. However, it was their 1989 album As Clean as They Wanna Be (a re-tooling of As Nasty As They Wanna Be) that began the prolonged legal debate over sampling. The album contained a track entitled “Pretty Woman,” based off of the well known Roy Orbison song of the same name. 2 Live Crew’s version sampled the guitar, bass, and drums from the original, without permission. While the opening lines are the same, the two songs split ways immediately following.^[2]

For example:

Roy Orbison’s version – “Pretty woman, walking down the street/ Pretty woman, the kind I’d like to meet.”
2 Live Crew’s version – “Big hairy woman, all that hair ain’t legit,/ Cause you look like Cousin Itt.”^[3]

In addition to this, while the music is identifiable as the Orbison song, there were changes implemented by the group. The new version contained interposed scraper notes, overlays of solos in different keys, and an altered drum beat.^[4]

The group was sued by the song’s copyright owners Acuff-Rose. The company claimed that 2 Live Crew’s unauthorized use of the samples devalued the original, and was thus a case of copyright infringement. The group claimed they were protected under the fair use doctrine. The case of Campbell v. Acuff-Rose Music came to the Supreme Court in 1994.
In reviewing the case, the Supreme Court didn’t consider previous ruling in which any commercial use (and economic gain) was considered copyright infringement. Instead they re-evaluated the original frame of copyright as set forth in the Constitution. The opinion that resulted from Emerson v. Davies played a major role in the decision.^[5]

"[In] truth, in literature, in science and in art, there are, and can be, few, if any, things, which in an abstract sense, are strictly new and original throughout. Every book in literature, science and art, borrows, and must necessarily borrow, and use much which was well known and used before." Emerson v. Davies,8 F.Cas. 615, 619 (No. 4,436) (CCD Mass. 1845)^[6]

Perhaps what played a larger role was the result from the Folsom v. Marsh case:

"look to the nature and objects of the selections made, the quantity and value of the materials used, and the degree in which the use may prejudice the sale, or diminish the profits, or supersede the objects, of the original work." Folsom v. Marsh, 9 F.Cas. 342, 348 (No. 4,901) (CCD Mass. 1841)^[7]

The court ruled that any financial gain 2 Live Crew received from their version did not infringe upon Acuff-Rose because the two songs were targeted at very different audiences. 2 Live Crew’s use of copyrighted material was protected under the fair use doctrine, as a parody, even though it was released commercially.^[8]

1990s

In the early 1990s, Vanilla Ice came under criticism for the unauthorised use of a sample from the Queen/David Bowie hit "Under Pressure". Vanilla Ice's case rested on the addition of one grace note not present in the original. No lawsuit was filed, but it is conjectured that Vanilla Ice agreed to pay Queen and Bowie if they agreed not to sue.

More dramatically, Biz Markie's album I Need a Haircut was withdrawn in 1992 following a US federal court ruling (Grand Upright Music, Ltd. v. Warner Brothers Records, Inc.) that his use of a sample from Gilbert O'Sullivan's "Alone Again (Naturally)" was willful infringement. This case had a powerful effect on the record industry, with record companies becoming very much concerned with the legalities of sampling, and demanding that artists make full declarations of all samples used in their work. On the other hand, the ruling also made it more attractive to artists and record labels to allow others to sample their work, knowing that they would be paid—often handsomely—for their contribution.

A notable case in the early 1990s involved the dispute between the group Negativland and Casey Kasem over the band's use of un-aired vocal snippets from Kasem's radio program America's Top 40 on the Negativland single "U2".

Cases have still emerged since then involving uncleared samples. In the late 1990s, The Verve was forced to pay 100% of their royalties from their hit "Bitter Sweet Symphony" for the use of an unlicensed sample from an orchestral cover version of The Rolling Stones' hit "The Last Time". The Rolling Stones' catalogue is one of the most litigiously protected in the world of popular music—to some extent the case mirrored the legal difficulties encountered by Carter the Unstoppable Sex Machine when they quoted from the song "Ruby Tuesday" in their song "After the Watershed" some years earlier. In both cases, the issue at stake was not the use of the recording, but the use of the song itself—the section from "The Last Time" used by the Verve was not even part of the original composition, but because it derived from a cover version of it, Mick Jagger and Keith Richards were still entitled to royalties and credit on the derivative work. This illustrates an important legal point: even if a sample is used legally, it may open the artist up to other problems.

2000

In the summer of 2001, Mariah Carey released her first single from Glitter entitled "Loverboy" which featured a sample of "Firecracker" by Yellow Magic Orchestra, no less than a month afterwards, Jennifer Lopez released "I'm Real" with the same "Firecracker" sample, Mariah quickly discarded it and replaced it with "Candy" by Cameo. The controversy here is that it is rumoured that Tommy Matolla, Carey's ex-husband, gave specific instruction to Lopez's producer to make the two songs as identical as possible. No one is sure if this is true, or why, possibly after Carey's departure from Columbia to Virgin, but only the parties involved know for sure.

In 2001, Armen Boladian and his company Bridgeport Music Inc. filed over 500 copyright infringement suits against 800 artists using samples from George Clinton's catalogue.

Public Enemy recorded a track entitled "Psycho of Greed" (2002) for their album Revolverlution that contained a continuous looping sample from The Beatles' track "Tomorrow Never Knows". However, the clearance fee demanded by Capitol Records and the surviving Beatles was so high that the group decided to pull the track from the album.

Danger Mouse with the release of The Grey Album in 2004, which is a remix of The Beatles' 'White Album' and rapper Jay-Z's The Black Album has been embroiled in a similar situation with the record label EMI issuing cease and desist orders over uncleared Beatles samples.

On March 19, 2006, a judge ordered that sales of The Notorious B.I.G.'s album Ready to Die be halted because the title track sampled a 1992 song by the Ohio Players, "Singing in the Morning", without permission.

Legal issues in practice

The most recent significant copyright case involving sampling held that even sampling three notes could constitute copyright infringement. Bridgeport Music Inc. v. Dimension Films, 410 F.3d 792 (6th Cir. 2005). This case was roundly criticised by many in the music industry, including the RIAA.

There has been a second important US case on music sampling involving the Beastie Boys who sampled the sound recording of a flute track by James Newton in their song "Pass the Mic". The Beastie Boys properly obtained a license to use the sound recording but did not clear the use of the song (the composition on which the recording is based including any music and lyrics). In Newton v. Diamond and Others 349 F.3d 591 (9th Cir. 2003) the US Appeals Court held that the use of the looped sample of a flute did not constitute copyright infringement as the core of the song itself had not been used. It seems that the position in law now is that with use of the sound recording any use without permission will constitute an infringement; however with the composition there must be some substantial use—the 'heart' of the song itself must be at least recognizable. This extends to both the music and the lyrics: a June 2006 case involving Ludacris and Kanye West held that their use of the phrases "like that" and "straight like that" which had been used on an earlier hip-hop track by another artist was not infringing use.

The New Orleans based company, Cash Money Records and former rapper Juvenile were taken to court by local performer DJ Jubilee (signed to Take Fo' Record Label) for using chants from his song titled Back That Ass Up. Both artist had used the same chant in each song, but Juvenile won the case because of the title's name change to Back That Azz Up, which sold 2 million copies. Because of the name change, Jubilee lacked evidence that Juvenile had stolen from him, and Jubilee could not earn Juvenile's income from his song.

Today, most mainstream acts obtain prior authorization to use samples, a process known as "clearing" (gaining permission to use the sample and, usually, paying an up-front fee and/or a cut of the royalties to the original artist). Independent bands, lacking the funds and legal assistance to clear samples, are at a disadvantage.

Recently, a movement—started mainly by Lawrence Lessig — of free culture has prompted many audio works to be licensed under a Creative Commons license that allows for legal sampling of the work provided the resulting work(s) are licensed under the same terms.

Producers on sampling

• "[Samples have] a certain reality. It doesn't just take the sound, it takes the whole way it was recorded. The ambient sounds, the little bits of reverb left off crashes that happened a couple of bars ago. There's a lot of things in the sample, just like when you take a picture—it's got a lot more levels than say, the kick-drum or the drum machine, I think. [...] Looking at a sampler the way it was used first—to try and simulate real instruments—you didn't have to get a session guitarist and you could just be like, 'Hey, I can have an orchestra in my track, and I can have a guitar, and it sounds real!' And I think that's the wrong way to use sampling. The right way is to get the guitar, and go, 'Right, that's a guitar. Let's make it into something that a guitar could never possibly be.' You know, take it away from the source and try to make it something else. Might as well just get a bloody guitarist if you want a guitarist. There's plenty of them." —Amon Tobin ^{dead link, view archive here}
• "Producers like Organized Noize mix samples and live instruments really well, but for me, it almost feels like a cop-out, because I'm a collage artist. It's like, 'Damn, if only I could find this one part. Well, maybe if I just had somebody paint it, and then I'll put it out.' That almost feels like cheating. Lots of times, I have trouble finding bass lines, because it's not very often on a record that there are good open bass lines. Sometimes I wish I could just have somebody come in and do what I want him to do on a bass line. It would be so easy. But what I do just keeps things much more challenging, I guess." —DJ Shadow http://remixmag.com/mag/remix_collage_constructionist/index.html
• "Cutting and pasting is the essence of what hip-hop culture is all about for me. It's about drawing from what's around you, and subverting it and de-contextualizing it." —DJ Shadow http://to-the-quick.binghamton.edu/issue%202/sampling.html
• "When I sample something, it's because there's something ingenious about it. And if it isn't the group as a whole, it's that song. Or, even if it isn't the song as a whole, it's a genius moment, or an accident or something that makes it just utterly unique to the other trillions of hours of records that I've plowed through" —DJ Shadow, 33 1/3 Volume 24: DJ Shadow's Endtroducing..., 2005
• "A lot of people still don't recognize the sampler as a musical instrument. I can see why. A lot of rap hits over the years used the sampler more like a Xerox machine. If you take four whole bars that are identifiable, you're just biting that shit. But I've always been into using the sampler more like a painter's palette than a Xerox. Then again, I might use it as a Xerox if I find rare beats that nobody had in their crates yet. If I find a certain sample that's just incredible—like the one on 'Liquid Swords'—I have to zap that! That was from an old Willie Mitchell song that I was pretty sure most people didn't have. But on every album I try to make sure that I only have 20 to 25 percent [of that kind of] sampling. Everything else is going to be me putting together a synthesis of sounds. You listen to a song like "Knowledge God" by Raekwon: it took at least five to seven different records chopped up to make one two-bar phrase. That's how I usually work." —RZA, The Wu-Tang Manual, 2004
• "For hip hop, the main thing is to have a good trained ear, to hear the most obscure loop or sound or rhythm inside of a song. If you can hear the obscureness of it, and capture that and loop it at the right tempo, you're going to have some nice music man, you're going to have a nice hip hop track." —RZA
• "Modern recorded music has evolved from focusing principally on musicianship and performance into an auditory collage where no sound is off limits. Sampling is simply another color on our palettes. Whether we're sampling old records, using advanced multi-sampling, or recording sounds ourselves, the final artistic product is paramount and should not be compromised in the face of any corporate legalities." —Sono
• "Let’s say I find a loop or something that I want to use—you attach yourself to a particular aspect or emotion that you find in it—part of it is looking for like-minded sounds and part of it is just laying things out in a way that kind of helps accomplish what you want. It’s what you can hear in a particular sound." —RJD2 http://www.themilkfactory.co.uk/interviews/rjd2iw.htm
• "I look at all the different parts and see how I can organize them in a way. It’s like mathematics. Very mathematic. It’s like graphs! You’re always searching for the combination that sounds best. It’s kind you set back, and feel the thing. If you want something to come in, you have to search for it, listen to it." —Blockhead http://www.trip-hop.net/interview-10-Blockhead.html
• "My music is based in hip hop, but I pull everything from dancehall to country to rock together. I can take a Led Zeppelin drum loop, put a Lou Donaldson horn on it, add a Joni Mitchell guitar, then get a Crosby, Stills & Nash vocal riff." —Prince Be Softly of PM Dawn, Musician magazine, June 1993
• "Sampling artistry is a very misunderstood form of music. A lot of people think sampling is thievery but it can take more time to find the right sample than to make up a riff." —Prince Be Softly of PM Dawn
• "Sampling's not a lazy man's way. We learn a lot from sampling, it's like school for us. When we sample a portion of a song and repeat it over and over we can better understand the matrix of the song." —Daddy-O of Stetsasonic, cited in Black Noise by Tricia Rose, Wesleyan Press 1994, p. 79
• "You got stuff darting in and out absolutely everywhere. It's like someone throwing rice at you. You have to grab every little piece and put it in the right place like a puzzle. Very complicated. All those little snippets and pieces that go in, along with the regular drums that you gotta drop out in order to make room for it." —Eric Sadler of Public Enemy's Bomb Squad, Black Noise by Tricia Rose, Wesleyan Press 1994, p. 80
• "It's a context issue, because not every sample is a huge chunk of a song. We might take a tiny little insignificant sound from a record and then slow it way down and put it deep in the mix with, like, 30 other sounds on top of it. It's not even a recognizable sample at that point. Which is a lot different from taking a huge, obvious piece from some hit song that everyone knows and saying whatever you want to on top of that loop. An example that's often brought up in court when we get sued over sampling is a Biz Markie track where he more or less used a whole Gilbert O'Sullivan song. Because it was such an obvious sample, it's the example lawyers use when trying to prove that sampling is stealing. And that's really frustrating to us as artists who sample, because sampling can be a totally different thing than that." —Beastie Boyshttp://www.wired.com/wired/archive/12.11/beastie.html
• "It’s pretty much impossible to clear samples now [in 2005]. We had to stay away from samples as much as possible. The ones that we did use were just absolutely integral to the feeling or rhythm of the song. But, back [on Odelay] it was basically me writing chord changes and melodies and stuff, and then endless records being scratched and little sounds coming off the turntable. Now it’s prohibitively difficult and expensive to justify your one weird little horn blare that happens for half of a second one time in a song and makes you give away 70 percent of the song and $50,000. That’s where sampling has gone, and that’s why hip-hop sounds the way it does now." —Beck http://www.pastemagazine.com/action/article?article_id=1816
• "I think it's wonderful, and it's a kind of poetic justice. When I was a teenager, I used to go down to Birdland and hear Miles Davis and Kenny Clarke. Later on, when I was at Juilliard, I heard John Coltrane. This had an enormous impression on me. In 1974, after a concert at Queen Elizabeth Hall, this guy with long hair and lipstick comes up to me and says, "Hi, I'm Brian Eno." Then in Berlin in 1976, after a performance of "Music for 18 Musicians," I met David Bowie. Now cut to the Orb and their generation. That's the way life ought to be. That's the way Bach and Bartok and Stravinsky worked, and it's how Kurt Weill worked. There should be a back-and-forth between what goes on in the street and the clubs and what goes on in the concert halls." —Steve Reich http://music.barnesandnoble.com/features/interview.asp?z=y&NID=113694

Types of samples

Once recorded, samples can be edited, played back, or looped (i.e. played back continuously). Types of samples include:

Loops

The drums and percussion parts of many modern recordings are really a variety of short samples of beats strung together. Many libraries of such beats exist and are licensed so that the user incorporating the samples can distribute their recording without paying royalties. Such libraries can be loaded into samplers. Though percussion is a typical application of looping, many kinds of samples can be looped. A piece of music may have an ostinato which is created by sampling a phrase played on any kind of instrument. There is software which specializes in creating loops.

Samples of musical instruments.

Whereas loops are usually a phrase played on a musical instrument, this type of sample is usually a single note. Music workstations and samplers use samples of musical instruments as the basis of their own sounds, and are capable of playing a sample back at any pitch. Many modern synthesizers and drum machines also use samples as the basis of their sounds. (See sample-based synthesis for more information.) Most such samples are created in professional recording studios using world-class instruments played by accomplished musicians. These are usually developed by the manufacturer of the instrument or by a subcontractor who specializes in creating such samples. There are businesses and individuals who create libraries of samples of musical instruments. Of course, a sampler allows anyone to create such samples.

Possibly the earliest equipment used to sample recorded instrument sounds are the Chamberlin, which was developed in the 1940s, and its more well-known cousin, the Mellotron, marketed in England in the 1960s. Both are tape replay keyboards, in which each key pressed triggers a prerecorded tape loop of a single note.

Musicians can reproduce the same samples of break beats like the "Amen" break which was composed, produced and mastered by the Winston Brothers in 1960s. Producers in the early 90's have used the whole 5.66 second sample; but music workstations like the Korg Electribe Series (EM-1, ES-1; EMX-1 and the ESX-1) have used the "Amen" kick, hi hat and snare in their sound wave libraries for free use. Companies like Korg have managed to use these samples for pitch, attack and decay and DSP effects to each drum part.

Most sample sets consist of multiple samples at different pitches. These are combined into keymaps, that associate each sample with a particular pitch or pitch range. Often, these sample maps may have different layers as well, so that different velocities can trigger a different sample.

Samples used in musical instruments sometimes have a looped component. An instrument with indefinite sustain, such as a pipe organ, does not need to be represented by a very long sample because the sustained portion of the timbre is looped. The sampler (or other sample playback instrument) plays the attack and decay portion of the sample followed by the looped sustain portion for as long as the note is held, then plays the release portion of the sample.

A common standard format for generating such sample sets is the soundfont protocol.

Resampled layers of sounds generated by a music workstation.

To conserve polyphony, a workstation may allow the user to sample a layer of sounds (piano, strings, and voices, for example) so they can be played together as one sound instead of three. This leaves more of the instruments' resources available to generate additional sounds.

Samples of recordings.

There are several genres of music in which it is commonplace for an artist to sample a phrase of a well-known recording and use it as an element in a new composition. Two well-known examples include the sample of Rick James' "Super Freak" in MC Hammer's "U Can't Touch This" and the sample of Queen/David Bowie's "Under Pressure" in Vanilla Ice's "Ice Ice Baby".

Samples of spoken word

Usually taken from movies, television, or other non-musical media, often used for humorous or atmospheric effect. For example, Goa trance often employs samples of people talking about drugs, spirituality, or science fiction themes. Industrial is known for samples from horror/sci-fi movies, news broadcasts, propaganda reels, and speeches by political figures (the band Ministry is notorious for sampling both the younger and elder George Bush). The band Negativland samples from practically every form of popular media, ranging from infomercials to children's records. A good example of this is "Civil War" by Guns N'Roses on their album Use Your Illusion II.

Unconventional sounds

These are not musical in the conventional sense - that is, neither percussive nor melodic - but which are musically useful for their interesting timbres or emotional associations, in the spirit of musique concrete. Some common examples include sirens and klaxons, locomotive whistles, gunshots, natural sounds such as whale song, and cooing babies. It is common in theatrical sound design to use this type of sampling to store sound effects that can then be triggered from a musical keyboard or other software. This is very useful for high precision or nonlinear requirements.

See also

• Sampling (signal processing) - Basic PCM theory
• Musique concrète - early development of fundamental importance in using recorded sound
• Amen Break - one of the most sampled tracks of all time
• Plunderphonics - in which samples are the sole source of sound for new compositions
• mashup - extensive page illuminating current practices of extensive sampling and their precedents
• Sound collage - production of new sound material using portions, or samples, of previously made recordings.
• Musical montage - is a technique where sound objects or compositions are created from collage.
• Sampler (musical instrument) - hardware and software platforms
• Illegal Art
• Creative Commons
• Fair use
• DJ Shadow - best know for his album Endtroducing..... which is entirely made of samples
• Daft Punk - very successful duo that constantly uses samples in their electronic music
• Compulsory Sampling License - would allow artists to freely sample without copyright owner's permission
• Interpolation
• Remix
• The Avalanches - Australian band known for its use of sampling.
• Cover version

Sampling in other contexts

• Collage - a work of visual arts made from an assemblage of different forms, thus creating a new whole.
• Papier collé - a painting technique and type of collage.
• Cut-up technique - an aleatory literary technique or genre in which a writing is cut up at random and rearranged to create a new text.
• Found footage - a method of compiling films partly or entirely of footage which has not been created by the filmmaker.
• Appropriation (art) - (Visual arts) often refers to the use of borrowed elements in the creation of new work.

References

External links

Free sample resources

• Free music downloads - Free music downloads, free samples and music loops (guitar, bass, synth and drum loops)
• Loopasonic - Free samples and loops download
• iBeat.org - Three levels of categorised open music wave samples.
• Atom Splitter Audio - Royalty free audio samples
• ccMixter.org 1,000s of samples licensed under Creative Commons

Look up who sampled who

• Second Hand Songs — a large, searchable database of original and new songs and artists.
• The-Breaks.com, AKA The (Rap) Sample FAQ — A searchable database that lets you search by sampling artist and sample.

The external links section in the Cover version article contains databases of cover versions.

Source

• Schloss, Joseph G. (2004). Making Beats: The Art of Sample-Based Hip Hop. Middletown, Connecticut: Wesleyan University Press. ISBN 0-8195-6696-9.
• Katz, Mark. "Music in 1s and 0s: The Art and Politics of Digital Sampling." In Capturing Sound: How Technology has Changed Music (Berkeley: University of California Press, 2004), 137-57. ISBN 0-520-24380-3
• McKenna, Tyrone B. (2000) "Where Digital Music Technology and Law Collide - Contemporary Issues of Digital Sampling, Appropriation and Copyright Law" Journal of Information, Law & Technology. Available online at:
• http://www2.warwick.ac.uk/fac/soc/law/elj/jilt/2000_1/mckenna/?textOnly=true