A
Acapella	A track containing only vocals - with no drums, melody or other accompaniment.
Acid	Prefix to a number of genre names (such as acid house, acid trance etc) in which the use of the infamous Roland 303 drum machine creates a distinctive sound.
Adapter	Any piece of hardware that allows two disparate pieces of equipment to work together. The RPM adapter is an example.
ADAT	The ADAT (a registered trademark of Alesis) is an eight-track digital tape recorder that caught the recording industry by storm when it was first released in the early 1990s. Today, with over 100,000 ADATs in use in recording facilities around the world, it is the most widely used professional digital recording system. The ADAT was the first product in the category now known as modular digital multitracks (MDMs). The ADAT system allows up to 16 ADAT units to be used in synchronization, enabling the user to build a very cost-effective multi-track recording environment. The transportability and modularity of the system makes it ideal for mobile recording and wherever space is limited. Digital transfer between ADATs in a system uses a optical fiber digital communication standard pioneered by Alesis which has become known as Lightpipe. The Lightpipe digital interface has been adopted by other manufacturers as a means of transferring digital data from other types of audio devices, such as mixers, synthesizers, and effect processors. The ADAT uses the S-VHS 1/2 inch tape format. This tape is similar in design to the tape used in consumer VCRs.
A/D Converter	An A/D (Analog to Digital) converter is an electronic device who's function is to convert analog voltages into a digital representation of electrical ones and zeros which can be stored, manipulated, and later retrieved or converted back to analog.
Agent	Also: Booking agent. A person who deals with the logistics of your DJ bookings, such as sending out demos and press packs, negotiating fees and hotels rooms and arranging flights. An agent usually takes about 15% of your fee in payment for these services.
Alesis™	Alesis invented the ADAT, and also makes power amps, drum machines etc.
Ambient	Ambient, or atmospheric electronica is background music: it was meant to be heard rather than listened to. The term is now extended to the more atmospheric techno music from 0 to 70 bpm. Illbient is a sub genre of ambient music invented by DJ Spooky in which the feel of the track is more disturbing then relaxing. Nu jazz is another sub genre of ambient. Ambient also refers to the beginning and end sections of a track where there are often no beats, or audible percussive rhythm.
Amplifier, Amp	This device amplifies (makes larger or increases) the signal from the mixer so that a pair (or pairs) of speakers can be powered. Some speakers are "self-powered," with built in amplifiers, but the majority require a separate amp to operate.
Amtrak	A really bad trainwreck. After the American rail company, AMTRAK.
Analog	Of, relating to, or being a device in which data are represented by continuously variable, measurable, physical quantities, such as length, width, voltage, or pressure. The opposite of digital.
Anthem	A track with a serious tone, having a dramatic crescendo, or build. Also a very well-known track that has come to typify a certain genre due to its popularity. Originally referred to choral arrangements,and other religious songs of praise.
Anti-skating	A feature found on professional turntables that prevents the needle from skipping across the record. Normally used in conjunction with the counter weight, the value of the anti-skate represents the force of the tonearm trying to skate away from the center of the record.
Attenuation	The reduction in sound level caused by earplugs, and measured in an NRR rating of decibels (dB). You should use earplugs that attenuate 20 dB of sound to protect your hearing in situations where you have to have difficulty hearing someone speak within 3 feet of you.
Aux or Line in	Abbreviation for auxiliary, meaning secondary or supplementary. In the case of DJ equipment such as a mixer or amplifier, the aux socket allows a secondary piece of equipment to be plugged in, a CD player for example. If you would like to record yourself mixing, your mixer should connect to the AUX socket on your hi-fi or stereo.

B
Back cue, to	See cue.
Backspin	See spinback.
Bar	A collection of beats. Commonly there are four beats per bar.
Battle	A hip hop or drum and bass DJing competition in which DJs compete against each other in short sets showcasing their skills and track selection.
Battle style	A way of orienting the turntables on their table so that the tonearm sides of the decks are furthest away from the DJ, as opposed to the ususal layout where the tonearm is to the right of the DJ. This method prevents the DJ's arms from brushing the tonarm and disrupting their set in the heat of a battle.
Beat	A unit of rhythmical noise in music, it can be made up of several notes or fractions of a note. The most common beats come four per bar (a 4/4 time signature).
Beat Counter	An electronic device that counts the beats per minute (bpm) of a track. Usually this is done by the user tapping a special pad with their finger in time to the music. The beat counter then works out how many beats per minute this would equate to. Very often beat counters and metronomes are comined in once device.
Beatmatch, to	The art of synchronizing and blending two separate tracks which to start off with had totally different speeds or tempos.
Beat juggle, to	This technique is performed by using two records and manipulating the arrangement of the elements (drum sounds, headnotes, vocals etc.) from both to create a new rhythmical composition. For example, in a very simple beat juggle one or more bars of record A are played, then the DJ quickly flips the crossfader to the beatmatched record B for one or more bars, then back to A and so on.
Bias	When the crossfader or cue mix is output at a higher volume on one channel it is said to be biased to that channel. e.g. If the crossfader is more to the right hand side. It is more biased to the right channel than it is to the left.
Binary mixer
Belt drive	One of the major differences between turntables is whether they are belt or direct drive. Belt drive turntables have their platter driven by a thick 'rubber band' compared to the DJ's preferred turntable, the direct drive, which is driven by a motor directly, giving increased torque for a faster pick up time. Belt drive turntables are not used in professional DJing due to their slow pick up time but audiophiles appreciate high end versions for their long belts which leaves the motor far away from the needle. This improves audio quality by significantly reducing motor noise picked up by the needle.
Black Lacquer	Black Lacquer is the standard record pressing industry technology. The process involves cutting a master plate (a mirror of the stampers), after which a stamper (a metallic plate that stamps the record) is made. This stamper is then punched into the hot vinyl to create the record. The advantages of this medium are obvious when creating vinyl for dance music. The pressing can be louder, and contains more visually appealing grooves.
Blank (or extra) stamper	A blank stamper is record pressing terminology for a pressing plate that contains grooves without music or you can have a blank plate without any grooves. These are used if you want a blank b-side on your record. An extra stamper is a copy of stamper that would be made if you wanted your record to be a double a-side. If you need a single-sided or double a-side record, you would be charged for mastering and plating for only one side and for the blank or extra stamper.
Blend, to	When a DJ mixes two tracks during the ambient or beatless part of one or both tracks, they are blending the two tracks, as opposed to beatmatching or any other method of mixing.
Body	The main part of a track's tune - between the build up and the breakdown. The "theme."
Booking agent	See: Agent.
Booth	The area where the DJ, her turntables, mixer and other equipment are located at a club, bar, rave or other event. In general it's best to stay out of the booth while a DJ is spinning, the same way you'd stay out of the kitchen in a restaurant. Unless you want someone to spit in your soup...
Booth output	The cable running from the mixer to the DJ's monitor, which allows the Dj to hear what they're doing.
BPM	Short for beats per minute. The bpm indicates the speed of an individual track. An easy way to count the bpm of a track is to count the number of beats in a 15 second timeframe and multiply that by 4 to get the number of beats in one minute. This is not especially accurate, and electronic beat counters are available to do this also.
Break	The part of a track where the song generally fades down to an ambient, or beatless section, or the main percussive elements are reduced or left standing by the removal of the melodic part of the track. Most tracks have two breaks in them, one at the beginning and one at the end, several bars before each end. These can be seen on the vinyl as smoother areas lacking in grooves when held under an angled light source.
Breakbeat	This genre is basically a beat with a "break" or gap in the continuity of the snare drums. The most common criteria for breakbeats are clear drums and percussion in a 4/4 measure. The snare usually plays on 2 and 4: so . 2 . 4. There may also be other snare hits in the measure that create even more complexity. Examples of breakbeat music include the genres breaks (also called breakbeats), funky breaks, nu skool breaks, dark breaks, the Bristol sound, trip hop, big beat, jungle, drum and bass and 2 step and their variants.
Breakdown	Part of a track after the intro and before the outro where the beat slows or stops, creating tension before the next section.
Breaks	Or: Breakbeat. A genre of music that incorporates a breakbeat rhythm and a bpm of around 120-140.
Build, build up	The areas after the breaks in a record where the track builds in melodic tension, before hitting the main body of the tune. This part of a tune is often considered sacred as they are the most exciting part of a track, alerting the dancefloor to the ensuing mayhem.

C
Cartridge	Also: Cart. The main component of the needle where vibrations from the stylus are converted into an electrical impulse. They're attached to the end of the tonearm.
CD	Compact disc.
CDR	Recordable compact disc.
CDRW	Re-recordable compact disc.
Center spindle	Or spindle. This is the blunt spike that points vertically from the center of a turntable. To play a record you place the hole in the middle of the record on the spindle.The spindle can be manupulated with the fingers to make fine adjustments to the speed of a record when beatmatching.
Channel	One line on a mixer, representing one turntable's output into the system.
Channel fader	The channel faders allow you to control the individual volume of each channel by the use of a slider or knob.
Channel selector	This allows you to choose between different input sources you have plugged into the back of your mixer.
Climax	The rise in tension within a track that begins in the first break and culminates in the start of the main theme of the tune. The exciting build up!
Closed back	In reference to headphones, this means that the ear cups are closed to keep out surrounding noise and keep in the noise of the music. It is essential that your headphones are closed back when playing in loud environments
Coffin	This is a heavy-duty case for carrying DJing equipment. Usually designed to carry two turntables and a mixer in a long shallow case resembling a coffin. The lid can be completely removed so that you can use your equipment with out having to take it all out and there are many different styles and brands available.
Contract	A very important piece of paper to the DJ, promoter and their agents. When properly worded this form legally binds them to the agreement they've made regarding fees, accommodation, transportation and so on. Have a look at ours!
Counter weight	The counter weight is situated towards the back of the tonearm and is responsible for the amount of pressure the needle exerts on the record. If your needle is skipping it can help to increase the pressure on it, but applying too much pressure can damage the record.
Crab	1) Noun. Crab (scratch). A type of scratching. Crab scratches can be performed singularly or sequenced. A close cousin of the twiddle, the crab scratch sounds like a quicker version of the transform and the flare. It involves quick taps on the fader knob with three or four fingers while cutting out the fader after each tap, using the thumb. 2) Verb. Crab, to. To perform a crab scratch.
Crate	A strong, usually metal and/or wooden, lockable box for carrying records. Some are tough enough to withstand the rigors of airline baggage handler roughness, others are not. To read more about crate selection go here.
Crossfader	Also: fader, x-fader. The crossfader is the main component of the mixer allowing you to fade between individual channels or play two channels simultaneously.
Cue, to	The act of finding the phrase within the next record you intend to play in the headphones.
Cue burn	The act of cueing a record up repeatedly in one spot, as in hip hop DJing and scratching, can wear the groove in the record at that point down. the resulting cue burn can cause the record to skip.
Cue level	The cue level controls the volume of sound playing through the headphones. Normally found on the mixer.
Cueing lever	This lever is used to gently lower the needle onto the vinyl without scratching it
Cue mix	The cue mix allows you to hear what is being played on each channel through the headphones. You can also listen to both channels simultaneously and some mixers allow you to pan betwween the cue and what is currently being heard through the main speakers.

D
DAT	Digital audio tape. A type of digital 2 track recorder that uses a small tape cartridge to produce high quality recordings in a compact format.
dB	dB stands for decibel which is the official unit used to measure the level of sound. This measurement is logarithmic to follow the response of the human ear. dB is a relative measurement to compare one level to another, for example gain from input to output. dBu is an absolute measurement referenced to a voltage standard where 0dBu = 0.775V rms. The console main outputs operate at 0dBu = '0' reading on the meters. dBV is a similar measurementbut refers to a 1V standard. It is common for consumer equipment to operate at the low standard of -10dBV (316mV). dBA refers to sound pressure level and is measured using the "A" scael that "hears" in the same way as the human ear.
Deafness	A temporary or permanent condition common in the music industry: protect your hearing with earplugs!
Deck(s)	Turntable(s).
Decibel	See dB
Demo	A tape or CD made by a DJ to show off her skills to a promoter or other person who may want to hire them for a gig. Learn how to make a good one here!
Digital	A description of data which is stored or transmitted as a sequence of discrete symbols from a finite set, most commonly this means binary data represented using electronic or electromagnetic signals. The opposite of analog (also: "analogue".)
Direct drive	One of the major differences between turntables is whether they are belt or direct drive. Direct drive turntables have their platter driven directly by a motor compared to the less expensive type of turntable (belt drive) that have their platter driven by a thick rubber band. Direct drive turntables have much better torque resulting in a far speedier pickup time, thus allowing for more accurate and efficient beatmatching. Don't waste your money on belt-driven turntables!
DJ	Disk jockey.
DMM	in record pressing terminology, Direct Metal Mastering involves cutting a groove directly into copper metal. Stampers are plated directly from the DMM Copper Master, eliminating two of the three plating steps required for lacquers. DMM Mastering produces records with lower distortion, superior high frequency response, longer program times and quieter surfaces than mastering on lacquers. This creates a "brighter", more pristine sound.
Downtempo	Also: Down tempo, down beat. Any genre of electronica of about 50-90 bpm.
Drum and bass	Also: D'n'b; drum'n'bass. The genre could be described as speeded-up breakbeats with a slower bassline. The speed of the drums varies from 140-170 bpm; the bassline is - sometimes - half of the speed of the drum. The drums have the breakbeat 1 2 33 4, which means that the 2 and 4 are snare or kick drum `on the floor', while the 1 sometimes and the 3 hardly always are syncopated drums (i.e. off the measure). The bassline is flowing smoothly or pumping energetically, originating from dub/reggae. This genre came from jungle and evolved from the early 1990s onwards. Today different sub genres of drum and bass are: atmospheric, intelligent, dolphin, 2 step, jump up, dark, ragga, and jazzy drum and bass.
Dub	Essentially reggae in the raw, this cultish, perennially popular form strips out the majority of the music's melody at the mixing desk, leaving behind the rhythm section and the residue of other instruments, often with massive layers of echo. Reggae records with crashing effects and decidedly eccentric arrangements date back to the ska era. By 1969-70 many producers were making largely instrumental music that was heavily dependent on the rhythm section (the Upsetters' 'Clint Eastwood' in 1970, for example), and it took only the addition of delay units such as the Copycat and Echoplate to create the dub boom. by 1991 a new breed of dub-inspired musicians, such as Jah Shaka, Sound Iration and the Disciples, had founded the 'new roots' movement, and placed the music back on the map, albeit with digital equipment and modern intentions.
Dub plate	Since the early days of reggae sound system the dub plate has been the format used to present exclusive or unreleased music, to aid in the promotion of that music, its artist and producer. Designed originally to be used as the positive master record from which a negative stamper would be made, dub plates were part of the record production process. The process begins with the artist, producer or label recording their product, once ready they would then take this to a "cutting house" where the resident engineer would then adjust any volume, equalization, compression and other enhancement followed by adjustments on a vinyl cutting lathe to determine the best sound quality for the tune. Most dub plates are 10" and contain one to five tracks. Their cost varies but in general they are about $40 each in the USA right now. Usually a DJ can play a dub plate 40-50 times before it wears out, and often dub plates are used as a status symbol among DJs, representing their ability to get tunes before they are available to anyone else, or produce their own tunes.
Dust cover	A hard plastic covering for your turntable that keeps dust out and stops it from getting damaged should anything fall on it.

E
Earplugs	To help prevent permanent damage to hearing you should wear earplugs that attenuate, or have an NRR, at least 20 dB of sound, on all occasions when you have difficulty hearing a normal speaking voice within three feet of you. To learn more about earplugs, read our article.
Electronica	This is a genre of music created using electronic devices such as drum machines, samplers and synthesizers.
Elliptical tip	This refers to the oval shape of one kind of stylus.
EP	Extended Play record.
EQ	1) Noun. Equaliser. Three dials on a mixer used to adjust the levels of bass, mid range and treble. There is a set of dials for each individual channel on the mixer. 2) Verb. "To EQ" is to adjust the equaliser on a mixer or sound system for the optimal sound quality.
Equaliser	See EQ
Exit or Outro	Part of a track's structure, the exit is the last bars where several elements are usually dropped out to leave a simpler version of the track to mix out of.
Extra stamper	See blank stamper

F
Fader	See crossfader or channel fader.
Fee	Payment for DJing. Currently in major metropolitan areas of the USA a local DJ can expect to be paid US$60-$150 to play for one or two hours, but fees rangng into the thousands are often paid to well known DJs. Negotiaste your fee ahead of time with the help of an agent and a contract.
Filter	Also: effects. A device by which a tune can be modified on output without altering it's tempo - many mixers come with effects filters, such as flange, reverb, echo etc. which can be applied to one or more channels at will to alter the sound of the track. Additional effects devices can also be routed through your mixer to add filters to tunes while you play.
Flange	A cousin to the chorus effect, flanging operates on the same time-delay principle. This time, though, the distance between the two identical inputs is constantly manipulated, creating distance between the sounds. The end result is — unlike the smooth, seamlessly-layered chorus — a discordant, textured wave of sound.
Flare	The flare scratch, named for DJ Flare, breaks up sound like the transform scratch. The DJ begins with the sound on, then bounces the fader to cut sound then bring it back in a split second. Each bounce equals one click. Measure your flare speed in the number of “clicks” you can manage in one stroke of your record hand.
Flight case	Or crate. A record carrying case designed to protect vinyl from the effects of heat and rough handling during transit. This term is also applied to cases used to carry tuntables, CDs and mixers.

G
Gabber	A sped-up type of techno with a 4/4 beat, generally around 175 bpm.
Gain	How much an electronic circuit amplifies a signal is called its "gain". Sometimes mistaken for volume, the gain boosts an incoming signal (from a microphone or an individual channel for example).
Garage	Not to be confused with "garage rock", a genre of punk music, "garage" is one of the most mangled terms in dance music. The term derives from the Paradise Garage, a legendary club which was located at 84 King Street, New York from 1976 till 1987. However the word garage has meant so many different things to so many different people that unless you're talking about a specific time and place, it is virtually meaningless. Part of the reason for this confusion (aside from various journalistic misunderstandings and industry misappropriations) is that the range of music played at the Garage was so broad. The music we now call "garage" has evolved from only a small part of the club's wildly eclectic soundtrack.
Gemini	Well established manufacturer of DJ equipment. Their products range from the beginner to the expert. Gemini produces some top quality turntables and a huge number of mixers catering to all levels of DJ.
Genre	A category of music, marked by a distinctive style, form, or content. A subcategory within a particular genre is called a subgenre. E.g. nu skool is a subgenre of breaks.
GruvGlide	A brand of record cleaner liquid that removes dust and prevents static on vinyl - this prolongs the life of needles.
Groove	Refers to one of the narrow channels on a vinyl record that carry the sound of the track, into which the stylus fits.
Ground, grounding	To prevent static electricity buildup in your equipment make sure it is properly grounded.

H
Hamster switch	This is a switch on some mixers that reverses the turntable so that the right channel swaps with the left. It is used in scratching to create effects.
Happy hardcore	Fast and furious four-beat hardcore with wacky, speeded-up, cartoony vocals added. The chipmunks on meth-amphetamine sound.
Hardcore	Hardcore has several meanings: 1. A lifestyle and subculture within the electronic music scene, revolving around hard and experimental musical styles, appreciation not only of hardcore techno, but other forms of hard music, as well as abstract music such as noise. The sub-culture itself borrows extensively from goth and punk, but with the influence of PLUR from the rave scene. 2. Hardcore,'Ardkore, UK Hardcore, UK Breaks. Music that was considered hardcore in the early 90s, and the small amount of music in the same genre that is still made today. Characterized by intense breakbeats, synth stabs, strings, chipmunk vocals, and sometimes hoovers, and big subbass. Around 130-160bpm. 3. Hardcore (as an overall genre of electronic music): a style characterized by hard beats, and often aggressive melodies and vocals, encompassing numerous diverse subgenres,including: Acid techno UK Hardcore Happy Hardcore Rotterdam (Dutch Gabber) Rottertrance (Dutch Gabber + Eurotrance) Gabber (hardcore techno, but also an umbrella term equivalent to Hardcore) Speedcore aka Brooklyn Speedcore, Deathcore, Terrorcore, Doomcore, Demoncore, Noisecore, Breakcore, Raggacore (such as Criminal Minds - Baptized By Dub, Genaside II - Narramine) Darkcore (such as Q Project - Champion Sound, Out of Order - The Dark Sheep) Skinnercore (characterized by being made by Robert Alan Skinner) and many others
Headphones	Placed on your head so you can hear an incoming track while mixing, headphones are an essential part of DJing. Choose a good quality pair with closed backs for better bass response and their ability to shut out external noise. Sony® makes good headphones.
Headshell	The headshell joins directly onto the tonearm providing a protective housing unit for the cartridge to attach to.
Hi-fi	Abbreviation for high fidelity. The reproduction of sound using electronic equipment that gives a faithful reproduction with little or no distortion.
Hip Hop	Hip hop is a cultural movement that began among urban African American and Latino youth in New York. The four main elements of hip-hop are MCing, DJing, graffiti, and breakdancing. Some consider beatboxing the fifth element of hip hop; others might add political activism, hip hop fashion, hip hop slang or other elements as important facets of hip hop. The term has since come to be a synonym for hip hop music and rap to mainstream audiences. They are not, however, interchangeable - rapping (MCing) is the vocal expression of lyrics in sync to a rhythm beneath it; along with DJing, rapping is a part of hip hop music. This genre of music is further defined by some of its originators here.
Hook	1. A catchy motif or refrain in a tune that is easily recognizable and instantly likeable. 2. To hook (up): The connect a mechanism (your mixer or turntables) to a power source by wiring. E.g. "I have hooked up the decks to the mixer but you can do the monitors."
House	1. A genre of music with a four quarter beat: 1 2 3 4 at about 120 bpm - about the speed of the heart of the dancer. On the 2 and 4, there is a snare drum or hand clap; in between 1 2 3 4 of the bass drum, you hear hi hats. The tracks are finished with some happy/swinging sounds, generally female vocals and a simple melody. Different sub-genres of house include: acid house, Euro house, hard house, progressive house, speed garage, and tribal house. 2. The word house also refers to the main club or event space, as opposed to the DJ booth. E.g. "The house volume is too low but these monitors are blowing my eardrums!"

I
Industrial	A genre of electronica marked by harsh rhythms, little melody, and nihilistic lyrics, if any. Industrial is characterized by deep and densely layered mixes that use samples of machine noises and industrial sounds. Industrial is also a subgenre of several other genres of music, such as industrial rock, industrial goth, etc.
Input sockets	Or inputs, ins. The input sockets can be found on the back of the mixer and on other pieces of audio equipment. In general terms this where you can plug things in.
Input selector	The input selector is found on the mixer normally situated along side the channel fader. The input selector enables you to switch from different input sources, another turntable or CD player for example. This means that a mixer with two channels can make use of more than two inputs.
Intelligent	So-called intelligent music (an adjective that can be added on to any genre, e.g. intelligent techno, intelligent ambient) is that which supposedly requires extra attention on the part of the listener to understand. With more complex or abstract rhythms it's appeal is often lost on the casual listener.
Intro	The beginning of a track before the main theme is introduced.

J
Jack	The receptacle for a plug found on a mixer, amp etc.
Juggle, to	See beat juggle.
Jungle	The Jungle was the name of a notorious area in the city of Kingston, Jamaica where reggae and dancehall beats evolved into what we now know as a form of drum and bass called jungle. Typified by rolling basslines and percussive snare drums, the style became popular in the early 1990's. Jungle is a genre in which MCs are popular. Lots of the words used by the jungle MC refer to the Jamaican slang for events taking place in Kingston - shootings and gang violence.
Junglist	A jungle DJ or someone who enjoys jungle or drum and bass music.
Jump start, to	Starting a record at full volume (audible on the house speakers) exactly at a beat, exactly when you want to (also referred to as cue starting). The record comes in and you have two records running in phase.

K
Kill switch	These switches will instantly drop one channel's output, or the bass, mid range or treble of a channel, from the mix at the flick of a switch - useful for effects where the DJ drops one track out for a bar, or a beat or more. Kill switches accomplish this more cleanly than trying to slide the crossfader over quickly.

L
Label	Or: lable (UK) 1. A record label, or artists management company. 2. The paper sticker in the middle of a record on which the artist name, title, and other information about the track are printed.
LED	LED stands for light emitting diode. LED's are often used in the output display as a means of indication of the channel volume levels.
Levels	The relative levels of highs, mids and bass output through the channels of a mixer when DJing. If you're asked by a sound engineer, the owner of the sound system or another interested party to "check your levels" you should take that as a subtle hint that you are playing with too much treble, bass ect. and should adjust the equalizers to improve the sound of your set. If someone takes the extreme measure of stepping behind the decks and adjusts the levels on your mixer for you, they are either being quite rude, or your ignorance of your levels is so great that the equipmnt is at risk of blowing.
Line or Aux	Input socket commonly found on DJ equipment (mixers etc.) and high quality audio equipment allowing line devices such as CD players to be connected.
Live PA	Playing live is producing music on the fly with the use of drum machines, synthesizers and so on. In reference to a tunrtable, if a deck is live, it is the one currently playing out through the house speakers.
Lock groove	Also: locked groove. A looped track on a record, usually containing a simple beat or melody, sometimes a breakbeat. Used in an intermediate form of performing in between mixing and live performance, or as an underlying beat in a 3 turntable setup.