AAC - Advanced Audio Coding is a digital audio file format and codec (see codec for definition). It is a compressed format designed to be a successor of the MP3 audio format as it is higher quality.
AIFF - Audio Interchange File Format is another digital audio file format and codec (see codec for definition). It is uncompressed and was developed by Apple so it is compatible with Mac computers and devices.
Alternating Current (AC) - an electric current which periodically reverses direction, in contrast to direct current (DC) which flows only in one direction. The usual waveform of alternating current in most electric power circuits is a sine wave, whose positive half-period corresponds with positive direction of the current and vice versa. Alternating current is the form of electric current that you’ll typically find when plugging into a wall socket. Audio and radio signals carried on electrical wires are also examples of alternating current. These types of alternating current carry information such as sound (audio) or images (video) sometimes carried by modulation of an AC carrier signal. These currents typically alternate at higher frequencies than those used in power transmission.
Analog - An analog signal is one in which the varying voltage is an analog of the acoustical waveform; i.e., it is continuously variable. Contrasted with a digital signal, in which binary ones and zeros represent audio or video information.
Aperture - How wide lenses diaphragm/shutter opens to allow light in. Almost all lenses on modern camera systems (except smartphones and many action cameras) have variable apertures and making the aperture smaller or larger will affect the amount of light that hits the sensor.
Apple ProRes 422 - A type of video codec (see codec for definition) that is uncompressed and mostly used for high quality playback and editing.
Audio Distribution Amplifier - (also known as an ADA) takes one audio signal, and outputs the amplified audio signal to multiple outputs.
Blu-ray - Blu-ray or Blu-ray Disc is a digital optical disc data storage format. It was designed to supersede the DVD format, and is capable of storing several hours of video in high-definition and ultra high-definition resolution.
BNC Cable - a video cable, with a locking connector used to transmit video signals to many different devices.
Brightness - an attribute of visual perception and for the quality of video or a photo that can often be controlled or set to make an image brighter or darker. This effect is usually used in tandem with contrast because the higher the brightness, the more the other darker objects appear washed out. You can usually control this on a video editing software and sometimes on a camera. See definition for contrast.
Chrominance/Chroma - the signal used in video systems to convey the color information of the picture, separately from the accompanying luma signal. See luminance/luma definition. Some video devices/monitors allow you control over chroma, allowing you to control the hue and intensity of the colors.
Chroma Key - Chroma key compositing, or chroma keying, is a visual effects/post-production technique for compositing (layering) two images or videos together, usually for the purpose of changing the background subjects or objects appear to be in. Green screens and blue screens are the most common colors to use for this effect because it is the color that is the least apparent on the human body.
Clip - "Clipping" means that the input (gain) levels were recorded too high for the capacity of a microphone or speaker, the waveform then gets recorded cut off and distorts the sound instead. Once the audio is recorded this way, it is not fixable, so make sure you are always setting your levels right!
Coaxial Cable - a type of electrical cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. BNC and RCA and RF cables are examples of coaxial cables with different connectors. Coaxial cable is a type of transmission line, used to carry high frequency electrical signals with low losses. It is used in such applications as telephones, internet networking, cable television, as well as radio transmitters and receivers.
Compression (Compressed/Uncompressed) - This has different meanings for audio recording and for computer files. In audio recording, it is the
Codecs - codecs are the format in which video or audio is encoded when being recorded or edited in a recorder or software and then exported into a playable file format. Compression codecs produce files that are smaller because it has deleted some of the data on the file to an agreed upon standard based on an algorithm, however, the quality is degraded to a degree that is barely noticeable. Uncompressed files are much bigger and the quality is not compromised. You would use compressed files in most contexts because it is more easily transportable over devices and the internet; uncompressed files take a lot longer to transfer. You must make sure that whatever device you are using will support the video codec you are using. We recommend H.264 as a compressed video codec because it is commonly used and supported by most devices, Apple Prores 422 as an uncompressed video codec. Some devices like media players will not support uncompressed video codecs. Audio formats are also encoded in compressed and uncompressed formats. WAV and AIFF are examples of uncompressed formats while MP3 and AAC are examples of compressed formats.
Color Balance - the adjustment of color intensity (typically red, green, and blue). An important goal of this adjustment is to render specific colors – particularly neutral colors – correctly. Hence, the general method is sometimes called gray balance, neutral balance, or white balance. Color balance changes the overall mixture of colors in an image and is used for color correction. Generalized versions of color balance are used to correct colors other than neutrals or to deliberately change them for effect.
Color Correction/Grading - Color correction is a process used in visual disciplines, that involves altering the overall color of the light sources. It is a process that in production, or while using analog cameras, uses colored gels that cover light sources. In post-production you can use video editing software to alter the colors of light sources. Typically the light color is measured on a scale known as color temperature, as well as along a green–magenta axis orthogonal to the color temperature axis. It can be a pretty creative process that contributes a lot to the overall mood or feel of an image or sequence.
Component - analog video signal that has been split on to three or more component channels. They do not carry audio signals so it is additionally paired with audio cables. VGA and RCA are common cables to carry component video. For RCA cables you will often see three RCA connectors one for each color of red, blue, and green (separate from red and white audio RCA cables). It is higher quality than composite video and even S-Video (see corresponding definitions of composite and S-Video).
Composite - analog video signal that carries standard definition quality video as a single channel. RCA cables commonly carry composite video. The yellow RCA connector is typically paired with audio cables that have red and white RCA connectors.
Connectors and Converters - most of the cables used in the analog lab have connectors you can use to convert them to other cable jacks. There are many connectors that convert cables to and from phono, RCA, and BNC.
Contrast - Contrast in visual perception is the difference in appearance of two or more parts of a field seen simultaneously or successively (hence: brightness contrast, lightness contrast, color contrast, simultaneous contrast, successive contrast, etc.). In the video context, when referred to as just contrast, it is usually in tandem with brightness. In this case it makes brighter objects brighter, and darker objects darker on a scale that you can control or set usually in a video editing program and sometimes on a camera.
CMYK - Stands for Cyan, Magenta, Yellow, and Key. It is a color model used in color printing and fields such as graphic arts and press. It is a subtractive color model because these are the colors that come from subtracting white light from its additive opposite RGB. Key is for black and represents the absence of light.
CRT Monitor/TV - a Cathode Ray Tube is a vacuum tube used as a display screen in a computer monitor or TV. The viewing end of the tube is coated with phosphors, which emit light when struck by electrons. The resulting color displayed on screen is derived by the intensity of the electron beams as they strike the red, green and blue phosphors and cause them to glow at each pixel location.
DAW (Digital Audio Workstation) - An electronic device or software that allows you to record, edit, manipulate, or add effects to sound or music. DAWs are used for the production and recording of music, songs, speech, radio, television, soundtracks, podcasts, sound effects and nearly any other situation where complex recorded audio is needed. Examples include Logic, ProTools, GarageBand, Adobe Audition, Audacity, and more.
Decibel (dB) - the unit of measure for sound intensity or loudness.
Direct Current (DC) - the unidirectional flow of electric charge. A battery is a good example of a DC power supply. Direct current may flow in a conductor such as a wire, but can also flow through semiconductors, insulators, or even through a vacuum as in electron or ion beams. The electric current flows in a constant direction, distinguishing it from alternating current (AC). There are devices used to convert direct current to alternating current and vice versa.
DV, Mini DV, HDV - a type of digital video tape format that converts the magnetic tape into a digital signal using varying types of video codecs. For clarity, These are three different types of video tape in varying cartridge sizes that use different video codecs, yet the purpose is the same as they convert the magnetic tape to a digital format. In earlier forms it used interlaced scanning much like older videotape cassettes, but progressive scan tape came soon after (see corresponding definitions for interlaced and progressive scan and video codecs).
Exposure - the amount of light allowed to hit the image sensor of your camera while taking a photo or capturing video. Longer exposure times results in a brighter image and more motion blur. Shorter exposure times results in a darker photo.
Feedback - This occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. You will most commonly hear feedback if you place a microphone in front of a speaker, as it will amplify any sound and feed it back into the microphone to amplify more, causing a feedback loop. It is a shrill sound in which the frequency of the resulting sound is determined by resonance frequencies in the microphone, amplifier, and loudspeaker, the acoustics of the room, the directional pick-up and emission patterns of the microphone and loudspeaker, and the distance between them. Video feedback can occur when pointing a camera at a television allowing the camera to see what it is filming and often distorts the image as a result. It is similar to pointing two mirrors at each other.
FireWire Cable - a cable for connecting digital devices, especially audio visual (A/V) to each other so that they can share information. It used to be faster than USB cables in transfer rate and also supplies a certain amount of power as well, as FireWire devices can be powered or unpowered. Speed aside, the big difference between FireWire and USB 2.0 is that USB 2.0 is host-based, meaning that devices must connect to a computer in order to communicate. FireWire is peer-to-peer, meaning that two FireWire cameras can talk to each other without going through a computer. Older computers have FireWire ports and some FireWire cables now have USB ends. There are 4-pin, 6-pin, and 9-pin FireWire cables. In the analog lab, you might use a FireWire cable to connect a camera, or certain DV tape decks to a computer or to each other.
Function Generator - a piece of electronic test equipment or software used to generate different types of electrical waveforms over a wide range of frequencies. Some of the most common waveforms produced by the function generator are the sine wave, square wave, triangular wave and sawtooth shapes. See waveform for more explanation.
Gain - In electronics, gain is a measure of the ability of a an amplifier to increase the power or amplitude of a signal from the input to the output port by adding energy converted from some power supply to the signal.
In audio, the gain is the input level of a signal as opposed to volume which is the output level. Gain is the first control audio goes through in the mixer while recording. The input level is important to set before recording any audio or doing any audio processing, because if you recorded with the gain too high, the sound you record will come out sounding grainy, distorted, or clipped (see “clip” and “grain” definition). Getting a clean signal for recording is always recommended as you can always add distortion later, whereas if the audio was recorded that way you will not be able to change it (in some cases you can fix certain amounts of noise and grain but it is rarely worth going through the effort).
In video, gain is also similarly the input level, but in terms of sensitivity to light in the camera’s sensor. See definition for ISO.
Gamma Correction - Gamma correction, or often simply gamma, is a nonlinear operation used to encode and decode luminance or tristimulus values in video or still image systems. A gamma value, represented using the greek letter > 1, is sometimes called an encoding gamma, and the process of encoding with this compressive power-law nonlinearity is called gamma compression; conversely a gamma value, represented using the greek letter < 1, is called a decoding gamma and the application of the expansive power-law nonlinearity is called gamma expansion. It involves brightness and contrast except that gamma specifically refers to the encoding and decoding system of operation on a camera or computer software and such.
Graphic EQ - A device that allows you control over a range of frequencies for live and recorded sound. This is also often emulated in software and plug-ins.
Grayscale - In digital photography/video and computer-generated imagery, a grayscale or greyscale image, is one in which the value of each pixel is a single sample representing only an amount of light, that is, it carries only intensity information. Grayscale images, a kind of black-and-white or gray monochrome, are composed exclusively of shades of gray. The contrast ranges from black at the weakest intensity to white at the strongest.
H.264/MPEG-4 - A type of video codec (see codec for definition) used for compression that is highly compatible with a lot of devices. It supports resolutions up to 8192×4320, including 8K.
HDMI Cable - High Definition Multimedia Interface cables allow you to transmit high quality data to other devices. You can use them with computers, monitors, projectors, TVs, and more to transmit uncompressed or compressed audio/video and computer files.
Hertz (Hz) - the unit of measure for frequency equal to one cycle per second.
High Definition (HD) - is video of higher resolution and quality than standard-definition. While there is no standardized meaning for high-definition, generally any video image with considerably more than 480 vertical lines (North America) or 576 vertical lines (Europe) is considered high-definition. 480 scan lines is generally the minimum even though the majority of systems greatly exceed that.
Interlaced Scan - The technique used in NTSC video in which the odd-numbered scanning lines of the video picture are displayed in one pass from the top of the screen to the bottom, and the even-numbered scanning lines are displayed on the second pass, to form a complete image. Contrast with “progressive scanning.”
Iris - The adjustable aperture setting on a video camera, see definition for aperture.
ISO - All image sensors have a range of sensitivity they can be set to in order to properly expose the image. The more your sensor is turned up, the more noise is added to the image and somewhat decreases the detail and dynamic range. ISO is an analog film term that was adapted into digital camera terms to essentially mean the gain or input level of sensitivity to light.
Keying/Compositing - is the combining of visual elements from separate sources into single images, often to create the illusion that all those elements are parts of the same scene. Live-action shooting for compositing is variously called "chroma key", "blue screen", "green screen" and other names. Some keying is performed live while some is done in post-production.
LCD Monitor - A flat panel screen that uses the liquid crystal display (LCD) technology and connects to a computer. Laptops have used LCD screens almost exclusively, and the LCD monitor is the standard display screen for desktop computers.
LCD TV - A flat panel TV that uses LCD technology or a rear-projection TV that is based on LCD microdisplay panels. All modern LCD TVs are wide screen high-definition TVs (HDTVs).
Luminance/Luma - the signal used in video systems to convey the light and brightness information of the picture, separately from the accompanying chroma signal. See chrominance/luma definition. Some video devices/monitors allow you control over luma, allowing you to control the brightness of an image or screen.
MIDI - A Musical Instrument Digital Interface is a way for synthesizers, samplers, or computers to record information and communicate with each other. For example, with a MIDI keyboard you may record a track, a computer will record the information as tones, and from that point on, you can replace the MIDI keyboard with a different instrument or patch that will playback the exact same information but with that instrument’s sound instead.
Modulation - In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted. Phase, amplitude, and frequency are all properties of a signal that can be modulated. The carrier signal holds no significant relatable information to us, except that which allows devices to detect it, but it does get imposed with the signal that does hold information, and thus allows devices to modulate the signal to get transmitted and demodulate the signal to get received. Most radio systems in the 20th century used frequency modulation (FM) or amplitude modulation (AM) for radio broadcast. Why modulation is used is because it can increase the strength of a signal and allow it to be possible to transmit many signals at once by assigning them each a frequency to be modulated, and then using a device to demodulate. This is also a technique of manipulating audio of certain instruments like synthesizers, but for electric guitars and basses it can be achieved through the use of pedals or computers.
Monophonic (mono) - Refers to audio that was recorded with one channel. Most microphones can only record audio in mono. Audio that is recorded in mono can be converted into stereo by . Depending on your speaker system, audio recorded in mono will either only play out of one speaker, or it will reproduce it and play the same thing out of both in a 2 speaker system.
MP3 - An audio digital file format and codec (see codec for definition) that is compressed.
Neutral Density (ND) Filter - a filter that reduces or modifies the intensity of all wavelengths, or colors, of light equally, giving no changes in hue of color rendition. The purpose of a standard photographic neutral-density filter is to reduce the amount of light entering the lens. Doing so allows the photographer to select combinations of aperture, exposure time and sensor sensitivity that would otherwise produce overexposed pictures. This is done to achieve effects such as a shallower depth of field or motion blur of a subject in a wider range of situations and atmospheric conditions.
NTSC - Named after the National Television System Committee. The body that set the American color TV standard in 1953. NTSC has become a descriptive name for television and video signals that conform to this standard. It is interlaced with a color encoding system used in Most North and South American Countries and has a frame rate of 60i or 30p.
Noise or Grain - In electronics, noise is an unwanted disturbance in an electrical signal. Noise generated by electronic devices varies greatly as it is produced by several different effects. The cause of noise comes from the circuitry in gain amplification and sometimes can be caused by dust in the electronic circuitry.
Image noise is random variation of brightness or color information in images, and is usually an aspect of electronic noise. It can be produced by the sensor and circuitry of a scanner or digital camera. Image noise can also originate in film grain especially when shooting darker images that are underexposed. Image noise is an undesirable by-product of image capture that obscures the desired information.
In audio, recording, and broadcast systems, audio noise refers to the residual low-level sound (four major types: hiss, rumble, crackle, and hum/buzz) that is heard in quiet periods of program. This variation from the expected pure sound or silence can be caused by the audio recording equipment, the instrument, or ambient noise in the recording room.
There is white noise, often seen and heard on a TV with no video source. There is pink and brown noise, and many other kinds of noise.
In some cases noise is desired, used in audio synthesis and as a visual effect.
Oscilloscope - a type of electronic test instrument that graphically displays electrical signals linearly so you can analyze it in real-time or played back. The electrical signal is converted to voltage to display the change of signal over time, with voltage and time as the Y- and X-axes, respectively, often on a 4 quadrant graph. The waveform can then be analyzed for properties such as amplitude, frequency, rise time, time interval, distortion, and others.
PAL - Stands for Phase Alternating Line, which is an interlaced frame color encoding system for analog television and video broadcast. It is used in most countries outside of the Americas and has a frame rate of 50i or 25p. It has a slightly higher resolution than NTSC at 576 visible lines compared with 486 lines with NTSC. So it has 20% higher resolution.
Panning - In audio terms, this controls whether audio is center, left or right. You can control the degree in which this audio is heard more to the left or right, or all the way to the left or right through a stereophonic speaker system or in a digital audio workstation (DAW) software i.e. GarageBand, Audacity, etc. In video terms, it is the movement of the camera from side to side from one location point to another.
Patch - May refer to analog or digital technology that is often used to describe a quality of sound on electronic instruments. Users will alter settings of their instruments to create a number of patches. The name comes from early analog synthesizers in which you would connect patch cables to inputs in order to route signals thus altering and building upon their sound.
Patch Cable - There are several types of patch cables for video and audio. They can be XLR, RCA, TS, or TS mini for audio. They can be RCA, BNC and WECO Standard VPC and MVPC for video. See corresponding pictures and definitions for each type of cables. There are many more but these are the most relevant to our analog lab!
Patch Panel, Patch Bay, Patch Field - A device or unit featuring a number of input/output jacks, to facilitate the connection of many different devices. Patch panels are commonly used in computer networking, recording studios, radio and television. If all devices are hooked up to the patch panel, you can easily patch audio, video, and computer equipment to each other in varying orders, without having to change any of the wiring on those devices. In those professional environments and our media labs, all the equipment is usually mounted onto racks, so instead of hunting around behind them in the dark trying to find the right jacks, all of the changes can be made at the patchbay. Using a patchbay also saves wear and tear on the input jacks of studio gear and instruments, because all of the connections are made with the patchbay. You can connect microphones, instruments, recording gear, effects, broadcasting equipment, video recording and switching equipment, cameras, distribution amps, and much much more with patch panels.
Phase - In a periodic wave, the fraction of a period that has elapsed. Describes the time relationship between two signals.
Phono/Phone Cable - Often used for TRS and RCA cables. Technically, phone cables are the other correct name for TRS cables as it comes from when telephone operation used patch cables for patching through calls. Phono cables are the other correct name for RCA cables as they connected to phonographs.
Power Conditioner - a device intended to improve the quality of the power that is delivered to electrical load equipment. In some uses, power conditioner refers to a voltage regulator with at least one other function to improve power quality (e.g. power factor correction, noise suppression, transient impulse protection, etc.). Conditioners specifically work to smooth the sinusoidal A.C. (alternating current) wave form and maintain a constant voltage over varying loads.
Preamplifier - Also called by its more descriptive name of an “A/V controller,” the A/V preamplifier is a component that performs surround decoding and lets you control the playback volume and select which source you want to watch and listen to.
Preview Out - On devices like video switchers and monitors and TVs, there is a preview out that allows you to preview footage that is being shot before switching it to your program out, which is what is being broadcast or recorded. The preview out is often connected to monitors in a control room. When multiple cameras or video sources are connected, you can assign them to the preview out using a video switcher. See corresponding definition of video switcher. Contrast with program out definition.
Program Out - On devices like video switchers and monitors and TVs, there is a program out that allows you to see the footage that is currently being broadcast or recorded. The program out is often connected to a TV or recording device in a control room. When multiple cameras or video sources are connected, you can assign them to the program out using a video switcher. See corresponding definition of video switcher. Contrast with preview out definition.
Progressive Scan - A method of creating an image on a video monitor by displaying the scanning lines sequentially from top to bottom. HD along with some SD digital cameras produce progressive scan footage. Contrast with “interlaced scanning.”
Quad Splitter or Color Quad Processor - A device that allows you to take multiple video outputs and split them four ways on one screen.
RCA Cable - A cable with connectors found on audio and video products. Signals transmitted via RCA jacks include line-level audio, composite video, and component video. They can either have RCA connectors on both ends or on just one end which may be other audio connectors like phono jacks or other video connectors like BNC jacks. The video signal is carried in the yellow RCA connector pin, while the audio is carried in the white (left) and red (right) RCA connector pins.
Receiver - A device that receives signals from multiple source component allowing you to select which signal you watch and listen to. It acts as an amplifier for other devices as well, receiving signals and amplifying them while also allowing you to control the playback volume and receive radio broadcasts.
Resolution - the total number of pixels in an image or video. Pixels are the little dots in an image displaying its color and therefore altogether make up the visual details of an image. The more pixels, the higher the resolution which results in better image quality as it is sharper and more detailed.
RF Cable - RF cables are a type of coaxial cable that is used to send radio frequency signals. RF cables are often used to send video information to a TV set.
RGB - The RGB color model is an additive color model in which red, green and blue light are added together in various ways to reproduce a broad array of colors. The main purpose of the RGB color model is for the sensing, representation and display of images in electronic systems, such as televisions, computers, monitors, cameras, scanners, and projectors. Color printers, on the other hand are not RGB devices, but subtractive color devices (typically CMYK color model). Primary colors when it comes to paints don’t apply here as those are chemical based reactions, RGB and CYMK are based in the physics of human perception of light and color.
RGB is a device-dependent color model: different devices detect or reproduce a given RGB value differently, since the color elements (such as phosphors or dyes) and their response to the individual R, G, and B levels vary from manufacturer to manufacturer, or even in the same device over time. Thus an RGB value does not define the same color across devices without some kind of color management.
Saturation - used in video editing to control the intensity of color in video. Increasing saturation makes colors in an image appear more vivid and intense, while decreasing saturation reduces the vividness of colors in an image, making it paler and paler until all color disappears. Completely desaturating an image converts it to black and white, or greyscale, leaving only the monochrome luma component. See greyscale and luma definitions.
SDI - Serial Digital Interface (SDI) is a standard for digital video transmission over BNC coaxial cables. Signals are uncompressed and are self-synchronizing between the source (transmitter) and destination (receiver). It has long range and is reliable as the cable connectors lock into place.
Shutter Speed - The shutter speed is the amount of time your image sensor is exposed to light. Or in the case of an electronic shutter, the pixels charge up from light at the start of the exposure and then they are discharged and read by the camera at the end of the exposure. Like aperture, shutter speed (also called exposure time) is variable and affects the amount of light captured by the sensor. The shutter speed also affects how much motion blur is in your image. A shutter speed that is half your frame rate is considered "normal", creating motion blur that is similar to how our eyes see blur. For example if you are shooting in 24P, which is 23.976 fps, a shutter speed of 1/50 or 1/48 sec would look very natural. Increasing the shutter speed to 1/100 sec for example, would result in an image that has less motion blur, but is also darker because the sensor has less time to expose the image.
Signal flow - The path an audio or video signal takes from the source to the output. It can include a variety of components and devices each of which can fail causing the signal not to reach its desired output. Instruments, cables, speakers, effect, and a variety of devices contribute to signal flow. It can involve putting all these devices in a very specific order. It can be particularly important for guitar pedals for example.
SMPTE Timecode - A set of cooperating standards to label individual frames of video or film with a timecode. The system is defined by the Society of Motion Picture and Television Engineers. They provide a time reference for editing, synchronization and identification. Timecode is a form of media metadata. The invention of timecode made modern videotape editing possible, and led eventually to the creation of non-linear editing systems.
The SMPTE family of timecodes are almost universally used in film, video and audio production, and can be encoded in many different formats, including:
Standard Definition (SD) - refers to the resolution quality of video between 240p-480p (pixels) before HD 1080p and 4K video quality.
Step Sequencer - a device (analog or digital) or software emulation that allows you to record and playback music in a sequence. This is often used with drum machines, bass machines, synthesizers, keyboards, or computer generated music and more. Some of those devices have built in sequencers.
Stereophonic (Stereo) - Refers to audio that was recorded with 2 channels, a left and right channel. Some microphones are for stereo recording and most wav recorders have stereo and mono recording capabilities. Most audio software allows you to take mono and stereo audio files and mix them in the software to then be exported as a stereo or mono file. The reason stereophonic speakers are used is to most closely imitate our own hearing as we have two ears. This also places a recording spatially in a room and spatially virtually as well. Many sound producers/engineers will use panning techniques to creatively control how instruments or sounds are coming through in the speakers thus giving the listeners a sense of space. For example, if you record a full band, you could choose to pan the guitar more to the left and more bass to the right. There are a lot of standard and classic techniques for panning in particular. See definitions for mono and panning.
Subwoofer - a speaker designed to produce low-bass frequencies.
Super VHS (SVHS) - S-VHS is an upgrade of VHS in which more picture detail (resolution) is recorded via increased bandwidth used for recording the video signal. As a result, S-VHS can record and output up to 400 lines of resolution, whereas standard VHS yields 240-250 lines of resolution. S-VHS recordings cannot be played on a standard VHS VCR unless the standard VHS VCR has a feature known as "Quasi-S-VHS Playback" although it will downscale the resolution. S-VHS tapes can be played on S-VHS VCR at full quality.
Surround Sound - a technique of sound reproduction that involves 3 or more channels of audio. The speaker system uses 3 or more speakers spread around spatially in a space so that there are at least two speakers in front of the listener as well as at least one speaker behind the listener. Some surround sound systems use a subwoofer as well to achieve more lower frequency sound. The most common 5.1 standard surround sound speaker system calls for 6 speakers, 3 in front of the listener, (left, center, and right), 2 in the back of the listener, (left and right), as well as a subwoofer whose position is not critical.
S-Video - an analog video signal with a 4 pin connector that, by separating the black-and-white and coloring signals, achieves better image quality than composite video, but has lower color resolution than component video (see corresponding definitions for composite and component video).
Switcher - A device used to select and transition between multiple audio and video signals or combine signals and sometimes add visual effects.
Time base corrector - Time base correction counteracts errors by buffering the video signal as it comes off the videotape at an unsteady rate, and releasing it at a steady rate. By adjusting the rate and delay using a waveform monitor and vectorscope, the corrected signal can now match the timing of the other devices in the system.
Time Code Generator - A device that generates a sequence of numeric codes generated at regular intervals by a timing synchronization system.
TS Cable (mono) - an audio cable with a 1/4 inch jack (often for instruments and patching) or 1/8 inch jack (mini). It is an unbalanced mono cable, meaning that it only has a positive signal wire and ground wire, so it is often noisier. It has one black stripe to indicate that it is only mono (one channel). TRS stands for tip, ring, and sleeve the connector parts of the plug that are for conducting.
TRS Cable (stereo) - an audio cable with a 1/4 inch jack (often for instruments and patching) or 1/8 inch jack (mini; often for patching, headphones, and aux cables). It is a balanced stereo cable meaning that it has a positive and negative signal wire as well as a ground wire, it is often less noisy. Stereo cables will only be recognized as stereo in stereo input jacks, they will not be recognized in mono input jacks. It has two black stripes to indicate that it is stereo (two channels).
Video Distribution Amplifier - (also known as a distribution amp or VDA) takes a video signal as an input, amplifies it, and outputs the amplified video signal to two or more outputs. It is primarily used to supply a single video signal to multiple pieces of video equipment. It adjusts the amplitude of a video signal to compensate for loss of signal in a video distribution system.
Video Mixer - A device that is used to select between multiple sources of video allowing you to switch between them and add transitions and effects. Besides hard cuts (switching directly between two input signals), mixers can also generate a variety of transitions, from simple dissolves to pattern wipes. Additionally, most video mixers can perform keying operations and generate color signals (called mattes in this context).
Voltage - Analogous to electrical pressure. Voltage exists between two points when one point has an excess of electrons in relation to the other point. A battery is a good example: the negative terminal has an excess of electrons in relation to the positive terminal. If you connect a piece of wire between a battery’s positive and negative terminals, volt- age pushes current through the wire. Current flow is the electron charge in motion through the conductor. One volt across 1 ohm of resistance pro- duces a current of 1 ampere.
Volume Unit Meter (VU) - a VU is a meter to show you volume levels on whatever you are listening to or recording.
Videocassette Recorder (VCR) - a device designed to to record and playback video and audio onto or from a videocassette, the videocassette being the cartridge that holds the video tape.
Video Tape Recorder (VTR) - a device designed to to record and playback video and audio onto or from a video tape. When someone refers to a VTR they usually mean open reel or 3/4” tape videocassettes.
WAV - A Microsoft and IBM audio digital file format and codec (see codec for definition) that is uncompressed.
Waveform - the visual representation of a sound wave. There are many types of waveforms i.e. sine, square, sawtooth, and triangle waves. These are merely mathematical concepts that are able to be created through electronic circuits. None of these, in their purest form, occur naturally in the world, as all sounds are made up of many sound waves, vibrating the air through the energy of their impact or source, that are imperfect and mostly asymmetrical, often changing over time. This altogether produces the timbre of the sound we hear.
WECO Standard VPC and MVPC - the standard Video Patch Cable (VPC) and Mini Video Patch Cable (MVPC) primarily used in patch bays for video.
White Balance (WB) - the process of removing unrealistic color casts, so that objects which appear white in person are rendered white in your photo. Proper camera white balance has to take into account the "color temperature" of a light source, which refers to the relative warmth or coolness of white light. Our eyes are very good at judging what is white under different light sources, but digital cameras often have great difficulty with auto white balance (AWB) — and can create unsightly blue, orange, or even green color casts. Understanding digital white balance can help you avoid these color casts, thereby improving your photos under a wider range of lighting conditions.
XLR Cable - an audio cable used for connecting microphones to a device. It is a balanced cable meaning it has a wire and pin for a positive, negative, and ground signal. This allows for a less noisy signal.
Zebra - Zebra patterning (or zebra stripes) is a feature found on some prosumer and most professional video cameras to aid in correct exposure. See exposure definition.