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Music Production Glossary

This glossary lists words commonly used in the context of modern music production and includes terms used when referring to Universal Audio products.

The list is in alphabetical order.



A/D – Acronym for Analog to Digital, which refers to the conversion of analog signals to digital data.

AAX – A plugin format native to Avid Pro Tools. It replaced the previously used format RTAS.

Acronym – A new denomination formed from the first letters of other words (e.g., GUI, ADAT, TRS, etc.).
ADAT – Acronym for Alesis Digital Audio Tape. ADAT was the name given to the Alesis-branded products of the 1990s which recorded eight tracks of digital audio on a standard S-VHS video cassette. The term now generally refers to the 8-channel optical Lightpipe connection that is used in a wide range of digital products from many manufacturers.

Additive Synthesis – A method of audio synthesis that outputs sound by mathematically adding harmonics, usually with sine waves, to each other.

ADSR – Acronym for Attack, Decay, Sustain and Release. It refers to the characteristics of envelopes usually applied to a sound to shape it over time. Can be applied to the amplitude, filter, pitch, etc.

AES (sometimes written as AES/EBU) – The name of a digital audio transfer standard jointly developed by the American-based Audio Engineering Society and the European Broadcast Union. Designed to carry two channels of 16-, 20- or, 24-bit digital audio at sampling rates of up to 192kHz, the most common AES physical interconnect utilizes a 3-conductor 110 ohm twisted pair cable, terminating at standard XLR connectors.

Aftertouch – A MIDI parameter that utilizes pressure applied to a key or pad after it has been initially played. It is then mapped to control a specific sound characteristic, such as volume, a filter cutoff point, the amount of reverb applied, etc.

AIFF – Acronym for Audio Interchange File Format. It is a high-quality audio file format created by Apple and similar to the WAV format.

Analog – Analog is defined as a replica or representation of something. In audio signals, changes in voltage are used to represent changes in acoustic sound pressure. Note that analog audio is a continuous representation, as opposed to the quantized, or discrete stepped representation created by digital devices.

API – Acronym for Application Programming Interface. A software layer between an operating system and third-party hardware (such as an audio interface) and/or software (such as a DAW). For example, a computer operating system’s audio API enables audio hardware and audio software from different vendors to communicate with the OS and each other.

Arpeggiator – A MIDI tool that turns any chord into individual notes played consecutively at a specified rate.

Arranger – In the context of a DAW, the Arranger is the main window area that presents the tracks (audio and software), the timeline of a project and its contents.

ASIO – Acronym for Audio Stream Input / Output. It's a computer sound card driver protocol for digital audio on Windows operating systems developed by Steinberg GmbH. It provides a low-latency and high fidelity interface between a software application and a computer's sound card.

AU – Acronym for Audio Unit. It is a plugin format created by Apple and is compatible with macOS/OSX only.

Audio Interface – A piece of hardware that can receive and output audio.

Authorize / Authorization – Authorizing the UAD/Apollo system updates the list of plug-ins owned by the user. UAD plug-ins must be authorized before they can be used.


Balanced – Audio cabling that uses two twisted conductors enclosed in a single shield, thus allowing relatively long cable runs with minimal signal loss and reduced induced noise such as hum.

Band Pass Filter – A filter type that combines a low-pass and a high-pass filter, allowing only a set range of frequencies of a sound through.

Bar – A musical term describing a measure of beats. In western music, this is typically a measure of 4 beats, but it can also vary depending on the time signature (i.e. 3/4, 5/4, 7/8, etc.)

Bit – A contraction of the words binary and digit, a bit is a number used in a digital system, and it can have only one of two values: 0 or 1. The number of bits in each sample determines the theoretical maximum dynamic range of the audio data, regardless of sample rate being used. Each additional bit adds approximately 6 dB to the dynamic range of the audio. In addition, the use of more bits helps capture quieter signal more accurately.

Bit Depth (or Bit Resolution) – The number of bits allowed for the dynamic range of an audio recording. Most modern music recorded in digital environments is formatted to 24-bit. A larger bit depth allows for a wider dynamic range.

Bitrate – The number of bits that are contained in an audio file every second, measured in kbps (kilo-bits per second). "320kbps" is an example of what an MP3 can store, while a WAV file usually has 1411kbps or a higher rate. Higher usually means better quality. Can be CBR (constant bitrate) or VBR (variable bitrate).

BNC – A bayonet-type coaxial connector often found on video and digital audio equipment, as well as on test devices like oscilloscopes. In digital audio equipment, BNC connectors are normally used to carry word clock signals between devices. BNC connectors are named for their type (Bayonet), and their inventors, Paul Neil and Carl Concelman.

Bounce – A term that refers to different audio sources being summed together and exported as a singular audio file.

BPM – Beats Per Minute. Refers to the tempo, measured in the number of beats per minute.

Browser – A feature that allows you to browse and tag files such as samples, presets, and stock content in your software.

Buffer (or buffering) – The transference of data in small batches instead of continuously. Buffering induces latency (delay) and is inherent in most digital audio systems.

Bus – A term used to refer to an auxiliary track that receives audio from multiple other sources from other tracks. For example, a bus may group vocals, piano, and synthesizers together after their individual processing. This bus will then allow for group effect processing, such as reverb, compression, etc.

Bus-Powered – This usually refers to a USB-connected device that draws its power from the USB connection itself, and does not require any kind of external power source.

Bypass – Term referring to temporarily disabling an effect so that the signal can be heard with the effect off. It is often found as a switch on effect plugins.


Channel (or Channel Strip)– An audio path going from a source (such as a plug-in) or an input to an output.

Chorus – A time-based effect that adds 2 or more shifting delays, hence creating a "detuning" effect.

Class A – One design technique used in electronic devices such that their active components are drawing current and working throughout the full signal cycle, thus yielding a more linear response. This increased linearity results in fewer harmonics generated, hence lower distortion in the output signal.

Class-Compliant (or Class-Compliance) – A term commonly used to describe a USB or Thunderbolt device which is 'plug-and-play'. Class-Compliant devices can be connected to the computer and will operate as expected without the need to install a driver.

Clock Signal – A signal that provides BPM information for devices to synchronize and stay in time together. One device usually outputs the signal and the others receive that signal. Can be transmitted over MIDI or CV.

Compression – A dynamic range effect that reduces the level of a signal when it exceeds a certain volume and increases the level when the signal is at a specified lower volume. It is often used to reduce the dynamic range of a sound and make its volume more consistent throughout.

Condenser Microphone – A microphone design that utilizes an electrically charged thin conductive diaphragm stretched close to a metal disk called a backplate. Incoming sound pressure causes the diaphragm to vibrate, in turn causing the capacitance to vary in a like manner, which causes a variance in its output voltage. Condenser microphones tend to have excellent transient response but require an external voltage source, most often in the form of 48 volts of “phantom power.”

Controller – A MIDI hardware device that controls the parameters of a piece of software or another device.

Control Voltage – Control Voltage, often abbreviated as CV, is an electrical signal used to change the characteristics of a sound depending on its voltage level. It is most often used in the context of analog / modular synthesizers.

Core Audio – The audio API for macOS.

Cutoff Frequency – A control on a filter that specifies where the frequencies will ramp off.


D/A – Acronym for Digital to Analog, which refers to the conversion of a digital data to an

analog signal.

DAW – Acronym for Digital Audio Workstation. A DAW is the software in which music is created, recorded, and edited in a modern studio environment. LUNA, Logic Pro, Cubase, Ableton Live, FL Studio, and many more are all DAWs.

Decibel (dB) – The standard measurement for loudness. Note that dB is a ratio measurement, always requiring a reference point from which to measure. Common dB measurements include dBFS (digital audio, where 0dB is clipping), dBm (decibels as referenced to milliwatt), dBV (decibels as referenced to voltage) and dB SPL (in acoustics, where 0dB is near silence).

De-esser – A type of multiband compressor that specifically acts on the frequency bands where sibilance is likely to be heard. It is used to remove higher frequencies dynamically.

Delay – A time-based audio effect that creates a series of echoes occurring at intervals one after the other.

DI – Acronym for Direct Inject or Direct Input, a recording technique whereby the signal from a high-impedance instrument such as electric guitar or bass is routed to an input. DI into mixer or tape recorder inputs often employ use of a DI box, which raises the signal to the correct voltage level at the right impedance.

Digital – Information or data that is stored or communicated as a series of bits (binary digits, with values of 0 or 1). Digital audio refers to the representation of varying sound pressure levels by means of a series of numbers.

Distortion – The processing of audio such that extra harmonics and loudness are added, creating a fuller or aggressive sound.

Dither – Minute amounts of shaped noise added intentionally to a digital recording in order to reduce a form of distortion known as quantization noise and aid in low level sound resolution.

Dry – Refers to a signal that is unprocessed, e.g., recording a dry signal. The antonym of a “wet” signal.

DSP – Acronym for Digital Signal Processing. Any audio processing that occurs in the digital domain by way of algorithms. DSP Accelerators are devices dedicated to digital signal processing. UAD-2 devices such as Satellites are DSP accelerators.

Dynamic Microphone – A type of microphone that generates signal with the use of a very thin, light diaphragm which moves in response to sound pressure. That motion in turn causes a voice coil which is suspended in a magnetic field to move, generating a small electric current. Dynamic mics are generally less expensive than condenser or ribbon mics and do not require external power to operate.

Dynamic Range – Refers to the number of decibels (dB) between the highest and the lowest point in a source's amplitude. A small difference means a lower dynamic range, while a larger difference means a higher dynamic range.


Early Reflections – Part of a reverb tail, the early reflections describe the initial body of reverberation that comes from natural or algorithmic reverberation.

Echo – A reflection of sound that arrives at the listener with a delay after the direct sound.

Effect – An effect (also called 'FX') modifies the audio signals it receives. For example, a reverb or chorus is considered an audio effect.

Envelope – A modulation source that affects the character of a sound (e.g. volume, waveshape or filter) and changes it over time.

EQ – Abbreviation for Equalization, a circuit that allows selected frequency areas in an audio signal to be attenuated or boosted.


Feedback – When an effect feeds the output signal back into the input signal, such as a delay or distortion, to exaggerate the effect. When a delay has more feedback, the delay's repeats are prolonged, thus it has a longer tail.

FET – Acronym for Field Effect Transistor. A type of transistor that relies on an electric field to control the shape, and hence the conductivity, of a channel in a semiconductor material.

Filter – An effect that only allows a certain band of frequencies to pass through it. Different filter types include low pass filter, high pass filter, bandpass filter, band reject and many more.

Firewire – FireWire is a discontinued high-speed real-time protocol for serial bus and isochronous/synchronous data transfer between enabled devices.                    

Firmware Software that is embedded in hardware.       

Flanger – A time-based effect that copies a sound with a few milliseconds of difference, in the range of 0ms to 5ms. It is then mixed with the original source, which creates additional harmonic content or detuning effects.

Flex Driver – Apollo technology that enables customized I/O mapping at the Core Audio driver level.

Flex Routing Apollo technology that enables its physical inputs to be routed to various physical outputs.

FM – Acronym for Frequency Modulation. A form of synthesis achieved by modulating the frequency of basic waveforms (e.g. sine waves) with each other, creating additional harmonic content. Largely popularized by the Yamaha DX7 synthesizer.

FPGA Acronym for “Field Programmable Gate Array.” A type of integrated circuit that can be programmed after manufacturing (“in the field”) to perform specialized functions.

Front End – Refers to a device that provides analog and digital input/output (I/O) to a digital audio workstation (DAW). Apollo is a front end device.


Gain – Initial level at which a sound source is being pre-amplified. Higher gain can result in overdriven sounds as it augments all of the harmonic content present in the sound source.

Gain Reduction – The resulting decrease in gain after downward compression is applied to a sound. The effect is usually counteracted by adjusting the output gain afterward.

Grain – An extremely short snippet of audio, often repeated in quick succession to achieve oscillation.

Grain Delay – A type of delay that repeats very short fragments of sound called grains, and plays them back in quick succession.

Granular Synthesis – A synthesis method that takes an audio file and cuts it into grains to create different waveshapes, then perceived as oscillation.

Graphic Equalizer – A type of EQ that separates the frequency spectrum into defined bands and allows gain adjustment for each band.

Graphical User Interface (or GUI) – A software window, panel, or screen containing controls where parameters are adjusted by the user.


Headroom – The number of decibels between the peak level of a sound and 0dB in audio. This term is used to describe the amount of gain that is available on the master channel for a mastering engineer to work with before the signal distorts.

Hi-Z – Abbreviation for High Impedance. Apollo’s Hi-Z input allows direct connection of an instrument such as electric guitar or bass via a standard unbalanced 1⁄4” jack.

High Resolution – In digital audio, refers to 24-bit signals at sampling rates of 88.2 kHz or higher.

Hz – Abbreviation for Hertz, a unit of measurement describing a single analog audio cycle (or digital sample) per second.


Impedance – A description of a circuit’s resistance to a signal, as measured in ohms, thousands of ohms (Kilohms), or millions of ohms (megohms).

IR – Acronym for Impulse Response. It is an audio file that can be loaded into a convolution reverb to apply a room or space’s natural reverb to any sound. It is useful to reproduce the specific acoustics of a room or environment without having to actually be in it.

I/O – Acronym for Input / Output. This refers to a section of a DAW or piece of hardware where different routing between channels can be configured.


JFET – Acronym for Junction Field Effect Transistor, a specific type of FET which has some similarities to traditional bipolar transistor designs that can make it more appropriate for use in some audio circuit designs.

Jitter – In the context of digital audio, it refers to the time distortion of recording / playback of a digital audio signal. It is essentially the deviations of time between the digital and analog sample rates.


kHz – Abbreviation for kiloHertz, the unit of measurement used in the context of Sample Rate.

Knee – This control on a compressor determines how hard the compressor acts when hitting the threshold. A hard knee setting activates the compressor instantly at the determined ratio, whereas soft knee ramps up the ratio as the signal gets louder, and allows for smoother, less obvious compression.


LFO – Acronym for Low-Frequency Oscillator. An LFO is an oscillator typically below the range of audio signals perceivable by human hearing. It is used as a modulation source to change the character of a sound over time; e.g. add vibrato or tremolo.

Lightpipe – A digital connection made with optical cable. This was a phrase coined by Alesis to make a distinction between the proprietary 8-channel optical network used in their ADAT products and standard stereo optical connectors used on CD players and other consumer products.

Limiter – An audio effect similar to a compressor at a ratio of ∞:1, meaning that no audio signal can pass the threshold. Typically the threshold is set to 0dB allowing no audio to distort and allowing maximum loudness if gain is applied.

Line Level – Refers to the voltages used by audio devices such as mixers, signal processors, tape recorders, and DAWs. Professional audio systems typically utilize line level signals of +4 dBm (which translates to 1.23 volts), while consumer and semiprofessional audio equipment typically utilize line level signals of -10 dBV (which translates to 0.316 volts).

Low Cut Filter – An equalizer circuit that cuts signal below a particular frequency. Same as high pass filter.


Mic Level – Refers to the very low level signal output from microphones, typically around 2 milliVolts (2 thousandths of a Volt).

Mic Preamp – The output level of microphones is very low and therefore requires specially designed mic preamplifiers to amplify their level to that needed by a mixing console, tape recorder, or digital audio workstation (DAW).

MIDI – Acronym for Musical Instrument Digital Interface. It is a standard protocol allowing for software and hardware devices to send data to one another, such as pitch, gate, tempo and parameter controls. When you plug a keyboard into your computer to play sounds in your DAW, it works via MIDI over USB.

Modulation – In music production, modulation refers to the adjustment of a parameter or sound characteristic over time, based on a source. A filter might be modulated by an LFO, for instance.

Modulation Wheel – A control on most keyboards and synths that allow a particular parameter to be modulated manually. For example, moving a modulation wheel on a KOMPLETE KONTROL keyboard might increase the amount of vibrato in a lead synth sound.

Monophonic – Term used to convey that only one note can be played at a time on a synthesizer, sampler, or instrument.

Mute – To turn a signal off. Mute stops the signal from being routed. 


Native – Refers to computer-based digital audio recording software controlled by the computer’s onboard processor, as opposed to software that requires external hardware to run.

Nyquist Frequency – Based on the Nyquist-Shannon theorem, which states that in order to adequately reproduce a signal it should be periodically sampled at a rate that is twice as much. The Nyquist frequency is the highest frequency (i.e. pitch or note) you wish to record. This is why, in the digital realm, the sample rate is twice the rate of the highest frequency in human hearing (20kHz), which is approximately 44100Hz or 44.1kHz. The higher the sample rate, the higher the frequencies can be recorded and played back.


Octave – A type of note interval that indicates the same note at a higher pitch. Octaves are always multiples of a given frequency. For instance, if A4 = 440Hz, then A3 will be 220Hz and A5 = 880Hz.

OS – Acronym for Operating System. The OS is the software used to control the computer hardware, such as macOS (Apple) and Windows (Microsoft).

Oscillator – An oscillator is a source generating a particular waveform in a synthesizer, such as a sine, sawtooth, pulse / square, or triangle. An oscillator’s pitch can be changed based on performed or sequenced notes, as well as modulation.


Pan –Abbreviation for Panorama. The process of moving a sound in the stereo field to the left or right speakers.

Parallel Compression – A compression method mixes the effected signal in parallel to the original sound.

Parametric EQ – EQ is the acronym for equalizer. It is a type of EQ that includes a set amount of customizable frequency bands. The shape, frequency, gain, width, and slope of these curves can usually be altered, allowing for very specific and surgical EQ processing. Most EQs included in a DAW as stock effects are parametric.

Patch Bay – A passive, central routing station for audio signals. In most recording studios, the line-level inputs and outputs of all devices are connected to a patch bay, making it an easy matter to re-route signal with the use of patch cords.

Phantom Power – A setting on audio interfaces and mixers that power condenser microphones with +48V of power to input if required. Condenser microphones generally require phantom power, whereas dynamic microphones don't.

Phase – Refers to the vibration of air caused by a generated sound and the position of the signal at a given time. It is measured in degrees, where 0º is the start point and 180º is the inversion of the signal. If two copies of the same sound have their phases set opposite each other (one at 0º and the other at 180º), they will cancel out each other and produce silence.

Phaser – A time-based effect that copies a signal, changes its phase, and mixes it with the original source. Essentially, this is a delay under 1ms that is often modulated by an LFO. Phasing introduces audible peaks / dips into the spectrum, hence altering the original source's harmonic content.

Phono – This is a synonym for the RCA inputs / outputs and cable format. You will find phono plugs on many audio devices such as turntables, cassette decks, and mixers.

Pitch – A synonym for frequency.

Pitch Bend – A control on instruments that allows the user to manually change the pitch of the note played.

Plug-In – Software that can be used inside a DAW to expand its functionality. It includes effects, sound generators, and utility devices. VST, AU and AAX are common plug-in formats.

Polyphonic – The ability of an instrument to play more than one note at once.

Preamp – Short for pre-amplifier. It is used to boost the gain of a signal before being recorded, processed, or amplified to a set of speakers.

Pre-delay – A setting on reverberation units that sets a delay before the initial early reflections of the reverb can be heard. It is used to create separation between an audio source and the processed signal as it passes through the reverb.

PWM – Acronym for Pulse Width Modulation. It is a synthesis process that changes the phase symmetry of a square or pulse wave.


Quantize – The process of taking MIDI / audio and shifting it so it is ‘on the grid’ and in time. Useful when MIDI or audio has been recorded with improper timing.

Quantization Noise – A form of digital distortion caused by mathematical rounding-off errors in the analog to digital conversion process. Quantization noise can be reduced dramatically by dithering the digital signal.


RAM – Acronym for Random Access Memory. A piece of hardware installed on a computer and used to store things momentarily when needed for faster access, such as KONTAKT libraries, for instance.

Ratio – A control on a compressor that determines how much gain will be reduced once the audio hits a set threshold. For instance, if a signal exceeds a threshold of 6dB and the ratio is set at 2:1, it will reduce the audio by 3dB.

Realtime UAD Processing – Universal Audio’s DSP + FPGA technology that enables UAD Powered Plug-Ins to run with latencies in the sub-2ms range. Realtime UAD processing provides the ultimate sonic experience while monitoring and/or tracking. Realtime UAD processing is a special function that is available only within the Console application.

Register / Registration – All UAD / Apollo devices must be registered into the user’s UA account before they can be used.

Reverberation (or Reverb for short) – A time-based effect featuring a series of echoes rapidly occurring one after the other and feeding back into each other. In the digital domain, there are two types of reverb, algorithmic which calculates everything via maths, and convolution, which uses an impulse response to capture the natural sound of a room and superimpose it onto another sound. Other physical methods exist as well, such as a plate or spring reverbs.

Ribbon Microphone – A type of microphone that works by loosely suspending a small element (usually a corrugated strip of metal) in a strong magnetic field. This “ribbon” is moved by the motion of air molecules and in doing so it cuts across the magnetic lines of flux, causing an electrical signal to be generated. Ribbon microphones tend to be delicate and somewhat expensive, but often have very flat frequency response.


S/MUX (or S-MUX) – Abbreviation for Sample Multiplexing. S/MUX is a method for transmitting two channels of high sample rate (88.2, 96, 176.4, or 192 kHz) 24-bit digital audio over a legacy optical lightpipe ADAT connection, which was originally designed to carry eight channels of 16-, 20- or 24-bit audio at 44.1 kHz or 48 kHz sampling rate.

Sample – A piece of pre-existing audio used as a sound in a composition. Samples can be any recorded material that is then repurposed or sequenced. The number of samples taken per second is determined by the device’s sample rate.

Sampler – An electronic instrument that can record or load samples and allows for their playback.

Sample Rate – The "speed" at which an audio file is recorded and played back in the digital domain. Sample Rate is directly related to the Nyquist frequency. The western standard for music is 44.1kHz, which is approximately double the limit of human hearing (up to ~20kHz).

Sequence – A series of samples, notes, or sounds that are placed into a particular order for playback.

Sequencer – A basic functionality of a DAW, which allows users to compose and organize samples, notes, and sounds to create music.

Sidechain – A tool on compressors that uses a second input to trigger when the compression occurs. For instance, a kick drum can be used to sidechain a reverb, hence creating a "pumping" effect on the reverb whenever the kick drum is played.

SPDIF (or S/PDIF) – Acronym for Sony/Philips Digital Interface Format, a digital audio transfer standard largely based on the AES/EBU standard. De- signed to carry two channels of 16-, 20- or, 24-bit digital audio at sampling rates of up to 192 kHz, the most common SPDIF physical interconnect utilizes unbalanced, 75 ohm video-type coaxial cables terminating at phono (RCA-type) connectors. 

Step – Steps are elementary time blocks. They are often used to apply quantization, usually in 1/16th note increments. Most DAWs possess a Step Editor in which notes are sequenced as steps, which can also be called a Piano Roll in some cases (e.g. in Logic Pro).

Subtractive synthesis – A form of synthesis that removes harmonic content from basic waves, such as sine, saw, square, triangle, etc. via the use of filters and amplifiers which can both be modulated by envelopes and LFOs.

Swing – In DAWs and sequencers, the Swing parameter allows you to shift some of the events in your Pattern to create a shuffling effect in order to achieve different grooves.


Tap Tempo – It is a control on a time-based device (e.g. delay or drum machine) that allows the user to tap multiple times to determine the tempo at which the device functions.

Threshold – It is the control on compressors, noise gates, and other devices that determines when the effect will start affecting the sound source at a specific decibel level.

Thunderbolt (Interface) – Thunderbolt is a hardware interface that allows the connection of external peripherals to a computer.

Timeline – In the context of a DAW, this term refers to the area going from left to right in an arrangement window where a track is being recorded and edited.

Transcoding – Converting one type of digital signal to another (e.g. from AES to SPDIF, or from ADAT to AES).

Transformer – An electronic component consisting of two or more coils of wire wound on a common core of magnetically permeable material. Audio transformers operate on audible signal and are designed to step voltages up and down and to send signal between microphones and line-level devices such as mixing consoles, recorders, and DAWs.

Transient – A relatively high volume sound impulse of extremely brief duration, such as a pop. Consonants in singing and speech, and the attacks of musical instruments (particularly percussive instruments), are examples of transients.    

Transport – In the context of a DAW, this refers to the area that contains the playback controls (e.g. play, pause, stop, rewind, fast-forward, etc.)

TRS – Acronym for Tip-Ring-Sleeve. A 1⁄4” phone connector with three conductors, typically used for balanced signal connections (e.g., I/O) or carrying two unbalanced signals (e.g., headphones).

TS – Acronym for Tip-Sleeve. A 1⁄4” phone connector with two conductors, typically used for unbalanced signal connections. Note that TS, like TRS and XLR, denotes the connector only and does not necessarily indicate the signal level of the connection. TS/TRS/ XLR cables are used for both low-level (e.g., microphones and instruments) and line-level connections.


UAD – Acronym for “Universal Audio Digital.” Used in reference to digital products created by Universal Audio. 

UAD-2 – A line of DSP accelerator products developed and manufactured by Universal Audio.

Unison – This term refers to Universal Audio’s exclusive preamp hardware/software integration technology that enables UAD preamp plug-ins reconfigure the physical input impedance, gain staging response, and other parameters of Apollo’s mic preamp hardware to match the emulated preamp’s hardware design characteristics with bi-direction control. In the context of synthesis, this refers to the functionality on synthesizers that layers a set amount of oscillators together at the same pitch with slight detuning in order to make a sound denser.

USB – Acronym for Universal Serial Bus. It is a standard socket and jack format on computers and devices that allow things to be connected to a computer and transfer MIDI information or data.

USB Hub – A device used to expand a single USB port into multiple USB connections. All devices connected through a USB hub share the bandwidth available through its respective USB port.


VCA – Acronym for Voltage-Controlled Amplifier. The section on an analog synthesizer that controls the amplitude of the output signal, and can be shaped by LFOs or envelopes.

VCF – Acronym for Voltage-Controlled Filter. The section on an analog synthesizer that controls the filtering of the generated signal, and can be shaped by LFOs or envelopes.

VCO – Acronym for Voltage-Controlled Oscillator. An oscillator whose pitch is controlled via voltage. The higher the voltage, the higher the pitch, and this can be shaped by LFOs or envelopes.

Velocity – It is the MIDI parameter for each performed and recorded note that determines the loudness of the notes. It can also be used to modify other parameters on synthesizers so as to affect a sound based on performance.

Virtual I/O – Apollo audio inputs and outputs that exist in software but not in hardware. Virtual I/O is used to route digital audio channels between Console and other audio applications.

VST – Acronym for Virtual Studio Technology. It is the plugin format developed by Steinberg, originally for Cubase that has now been adopted as one of the industry standards.


WASAPI – Acronym for Windows Audio Session API. It is Microsoft’s multi-channel audio interface for communication with audio devices, i.e. an audio driver.

Wavetable – It is a series of waveform cycles that can be scanned through and morphed into each other.

WAV – Acronym for Waveform Audio File Format. It is the standard lossless audio file format in the digital domain. Samples, stems, and other audio files typically are recorded or come in the WAV format.

Wet – Refers to a signal that is processed, e.g., recording a wet signal. The opposite of a dry signal.

Word Clock – A dedicated clock signal based on the transmitting device’s sample rate or the speed with which sample words are sent over a digital connection.


XLR – It is the standard electrical connector in audio that features three pins and is round. Found on many mixers and audio interfaces, usually used to connect microphones or speakers.




Zero-Latency Monitoring – This refers to the functionality on audio interfaces that let you monitor the audio signals during the recording process before it reaches the analog-to-digital converters (ADC). This is beneficial when recording audio in the digital domain as there will always be some delay when recording audio into a DAW.