In this brief glossary we explain some of the key terms that will help you understand more about audio technology. Think something is missing? Let us know at blog@teufel.de.
| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z|
| Abbreviation | Explanation |
|---|---|
| AAC | Short for "Advanced Audio Coding". This audio format allows for more sound quality than an mp3 file with the same data size. |
| Acoustic power | Also known as sound power, this is an acoustic value that indicates the sound energy per time unit of a sound source. The standard unit for measurement is the watt. |
| Active speakers | A kind of speaker with the amplifier built in, meaning no external receiver or amp is required. |
| Air gap | In loudspeaker construction, the air gap is the narrow gap between permanent magnets in which the moving coil can vibrate. |
| ALAC | Short for Apple Lossless Audio Codec. Designation for a sound format developed by Apple for lossless data compression compared to the original signal. |
| Ambience | Diffused background noise in film/radio/television, such as road noise. |
| Amplifier | Common term for a device that amplifies incoming audio signals to make them audible. |
| Active Noise Canceling (ANC) | A technology common in headphones which filters out noise from the environment by taking input from microphones on the headphones and adding a reverse sound wave to cancel out unwanted noise. |
| A synonym for Active Noise Canceling | |
| aptX | Quality feature of an audio signal transmitted via Bluetooth. The original signal is transmitted in CD quality. |
| ARC | Short for Audio Return Channel. Enables two-way signal transmission with just one HDMI cable. |
| ASMR | Short for "Autonomous Sensory Meridian Response". Indicates a sensory reaction which can be triggered by specific sounds, such as whispering. |
| Audiogram | Also known as the hearing curve, this describes a person's subjective (frequency-dependent) hearing ability. |
| Auditory perception | The overall sensory experience of sound. |
| Auto-Tune | Software for post-correction of the pitch of music in digital recordings. |
| AUX | The AUX input (aux is short for auxiliary) is an analogue input for stereo audio signals. |
| Banana plugs | Colloquial term for 4mm R-pin. Connects detachable loudspeaker cables e.g. to an amplifier. |
| Band | Band is short for frequency band and refers to a certain small frequency range within a larger total frequency range. |
| Bass | The frequency range of audible sound below about 200 Hz. |
| Bass reflex tubes | Bass reflex speakers are loudspeakers that amplify sound waves (usually) radiated through tunnel-like openings by reflection. |
| Bead | The bead is the part of the speaker that connects and seals the diaphragm and basket. |
| Beats per minute (bpm) | Describes the tempo of a piece of music. |
| Bi-amping | Special cable connection method between amplifier(s) and speakers. In bi-amping, two power amplifiers are connected to a pair of speakers, with each amplifier amplifying its own frequency range. |
| Binding posts | An alternative method of cabling to push terminals. The end terminal has a red or white binding post where the cable ends are stuck and screwed down tight. |
| Bit rate | The bit rate is the output quantity of audio or video signals for digital multimedia formats per time unit. The unit of measurement is called "bit per second" (bit/s or bps). |
| Bi-wiring | Special cabling method between amplifier and speakers. With bi-wiring, individual frequency ranges are divided into different cable paths and fed together to the speaker. |
| Cone speaker | Dynamic speaker with a cone-shaped radiator, i.e. a domed cone. |
| Capacitor | A capacitor is an electrical component which stores electrical charge. It is used in crossovers for speaker construction. |
| CEC | Short for "Consumer Electronics Control". CEC is a cross-device control of at least two devices connected via HDMI with one remote control. |
| Center speaker | The speaker that goes right above or below the screen in a Surround Sound setup - generally handles dialogue. |
| Chassis | Term for the fixed housing of a speaker. Also called a cabinet or cab. |
| Class D | |
| Clipping | Clipping happens when the amplifier is overloaded. The signal level is so high that the radiator hits other components. This results in unclean sound. |
| Cone | Driver radiators can be made flat, cone, concave or sandwich shaped. Cone speakers are primarily for bass or midrange drivers. Cone radiators produce audio pressure in the air. They are fixed to the chassis using a bead. |
| Crossfader | An element on a mixer that allows a gradual transition from one source to another. |
| Coaxial driver | Coaxial drivers consist of at least two drivers arranged on a single axis. Acoustically, this is an advantage, as the coaxial driver acts as a point source of sound and therefore reproduces sound in a more natural way. |
| Comb filter | A filter that can pick out pre-defined frequencies from sound signals. |
| Cone speaker | A common form of driver in which the radiator is designed in a conical shape. |
| Critical frequency | The upper or lower limit of the frequency range up to which a speaker can reproduce an undistorted audio signal. |
| Crossover | The crossover is a component in a speaker that divides electroacoustic input signals into different frequency ranges and feeds them to the corresponding drivers. |
| DAC | A DAC is a digital analog converter, which takes digital inputs and outputs analogue audio signals. Used to produce clean audio output for HIFI listening. |
| DAB/DAB+ | Short for Digital Audio Broadcasting, this is a radio standard popular mainly in Europe that was meant to replace FM. |
| D'Appolito Design | A type of speaker design where the tweeter is in between two midrange drivers. |
| Decibel | The decibel (dB) is a unit of measurement for the loudness of a sound, named after Alexander Graham Bell. |
| Decoder | In audio devices, this device converts digital signals into analog ones. AV receivers generally have a built in decoder. Older amplifier models also have the decoder in the pre-amp. |
| Decoupling | Speakers can be decoupled from the floor to reduce the transmission of vibrations to the floor. |
| Diaphragm | Also known as a radiator, this is the part of a speaker driver that produces sound waves. |
| Diaphragm material | Whereas tweeter diaphragms are supposed to have fast excursion, bass driver diaphragms primarily have to move a lot of air. Tweeter domes are made of things such as carbon fiber, NAWI cellulose, layered cellulose fibers, or special membranes, but others can be made of titanium, aluminum or beryllium. Midrange drivers and tweeters can be made of polypropylene, aluminum, PVC, polystyrol, Kevlar, titanium, Rohacell carbon cone sandwich, long-fiber paper, as well as fiberglass. |
| Diffraction | When sound waves hit an obstacle or an object with an opening and the waves reflect off it in different directions. |
| Direct emitter | A direct emitter is an audio source that produces sound in only one direction. |
| Discman | Colloquial term for a portable CD-Player, originally developed by Sony. |
| Distortion factor | The harmonic distortion factor indicates how much the output signals deviate from the input signals, i.e. by what percentage they are distorted. |
| Dolby Atmos | The latest Dolby sound standard for home cinema. With Dolby Atmos, an unlimited number of audio tracks can be employed. The defining feature of this format is the track meant to come from above. |
| Dolby Digital (Plus) | This is Dolby's codec for the digital transmission of 5.1 audio signals, especially during streaming. The newer Dolby Digital Plus standard also allows the transmission of 7.1. audio signals. |
| Dolby Pro Logic | An audio codec from Dolby. Dolby Pro Logic can decode room sound information from a stereo source. |
| Dolby Surround | Dolby Surround is an outdated analogue multi-channel sound system that can accommodate four audio channels in two soundtracks. |
| Dolby Vision | Dolby TrueHD was developed by Dolby Laboratories specifically for the soundtracks of HD DVDs and Blu-ray Discs. According to the manufacturer, it is lossless. |
| Dome tweeter | A design for treble drivers, aka tweeters, shaped like a dome. |
| Down-firing subwoofer | In a down-firing subwoofer, the speaker cone is directed towards the floor. The sound signal is immediately reflected and thus perceived as more omnidirectional. |
| DPU Technik | Bass reflex technology developed by Teufel in order to avoid flow noises. |
| DSP | Short for "Digital signal processor". Computer chip for sound control. |
| DTS HD | Short for "Digital Theater Systems High Definition". DTS HD is a multi-channel digital audio system, specifically designed for Blu-Ray discs and HD DVD, and the competing format to Dolby True HD. |
| DTS:X | DTS: X is a sound format based on audio objects and is therefore not bound to a certain number of speakers. This sound format is an alternative to Dolby Atmos. |
| Dust cap | A part of a speaker which connects to the diaphragm and keeps foreign particles from entering the driver |
| Dynamore | Dynamore is a patented method developed by Teufel for creating a more 3D sound experience from smaller systems. |
| Echo | An echo is audible when reflections from a sound source are delayed so much that the ear perceives the reflection as distinct from the original sound. |
| Equalizer | An equalizer (EQ) is an analogue or digital user interface that allows you to manually change individual frequency ranges, for example, to emphasize the bass. |
| Fade | A slow, manual or automatic change of volume. |
| Feedback | An audio effect created when a closed loop exists between a sound producing element and a sound receiving element - for example, improperly set up speakers/PAs/amplifiers and microphones. |
| FLAC | Short for "free lossless audio codec ". FLAC is an open audio format for lossless storage. |
| Frequency range | The frequency range indicates a precisely defined range between and the highest tone a speaker can reproduce and the lowest. For example, from 45 - 20000 Hz. |
| Front-firing subwoofer | A subwoofer with the driver cone facing forward, which may cause less vibration of the building. |
| Fuzzbox | A type of effect pedal used to give electric guitars a more distorted sound |
| Goniometer | A device for measuring angles as well as the electric phase positioning for stereo audio |
| Ground loop | A phenomenon when multiple devices are in one system and an undesirable humming sound is produced. |
| Haas effect | The Haas effect, or the Precedence Effect, is a psychoacoustic Effect described by Helmut Haas as the ability of our ears to locate sounds coming from anywhere around us. |
| HDMI | Multi-vendor interface to transmit (especially) video signals. Abbreviation for "High Definition Multimedia Interface". |
| HDR | Short for High Dynamic Range. Dynamic image contrast control on monitors. HDR requires HDMI 2.0 or higher. |
| Headset | A headset is a pair of headphones with an integrated microphone. |
| Hertz | Hertz (Hz) is the (derived) physical unit for the frequency. Hertz are the number of repetitive oscillations per second. Named after the German physicist Heinrich Hertz. |
| Hi-Fi | Short for High Fidelity. Hi-Fi is a quality standard in audio engineering. |
| Hi-Fi rack | A Hi-Fi rack (also called a Hi-Fi shelf) is a piece of furniture mostly for private use, on which audio devices such as amplifiers, receivers, etc. can be placed. |
| Horn speakers | A horn speaker is a type of speaker in which one or more drivers are designed in the form of a funnel (like a horn). Horn speakers have a high dynamic range and low power consumption. |
| Impedance | Resistance to alternating current measured in ohms - the ratio of electrical voltage at an end point to the total power draw |
| In-ears | Popular headphone design. The earpieces are inserted directly into the ear canal for listening. |
| In-ear monitoring | A kind of monitoring using in-ear headphones |
| Integrated amplifier | Some speakers, generally referred to as "active" speakers" have amplifiers built in, making external amplification systems unnecessary |
| Interaural | Latin for "between the ears". This term plays a role in describing the localization of auditory events. |
| Interference | Interference is a superposition of at least two sound waves of the same frequency. |
| ISRC | International Standard Recording Code (ISO 3901) is a digital identifier used in the subcode of an audio CD. |
| Jitter | Jitter refers to the fluctuation of the stroke frequency, which can have a negative effect on the sound. |
| Klippel | A measuring system for testing speakers made by the Klippel Corporation. These high precision, expensive devices test behavior of speakers beyond what can be reliably heard by a human ear. |
| Latency time | An important term in digital audio tech (for example for DACs). The latency time of an audio system is the difference in time between when a signal is fed into a system, and when it is produced by the system. Depending on application, this kind of delay can be very undesirable. |
| Limiter | A device that limits the maximum amplitude of a signal. |
| Low fidelity (Lo-Fi) | The antonym of Hi-Fi - can be used to describe recordings with more basic equipment, or recordings meant to mimic more primitive recording techniques. |
| Low frequency | Frequencies between 20 - 20.000 Hz. |
| MIDI | Short for „Musical Instrument Digital Interface". MIDI is a digital interface for the synchronisation of electronic musical instruments or effect devices. |
| Minimoog | The Minimoog is an instrument that was invented by physicist Robert Moog in 1970. |
| Monitor | Monitors are a kind of speaker or headphone used to monitor the sound in a studio or concert so the performers can hear what they're playing. Generally controlled with a mixer to avoid creating feedback. |
| Moving coil | The moving coil is the component of a driver that provides motion |
| MP3 | A method of compressing audio files that is popular around the world. |
| Multi-room audio | Multiroom systems are linked speaker systems (possibly in different rooms) which can be controlled by a central unit. |
| Music cassette | An older method of storing audio recordings which is enjoying a small renaissance. |
| Neodymium magnet | A magnet made from the chemical element neodymium, which is highly rare. Neodymium magnets are particularly well-suited for speak construction because they can generate strong magnetic fields from small devices. |
| Noise-cancelling headphones | In acoustics, noise cancellation is usually associated with headphones. Noise-cancelling headphones are designed to reduce external noise. They use passive and active technology. |
| Noise floor | refers to the inherent noise of an individual speaker which is drawing power (watts) but not producing a signal. Alternatively, can refer to the inherent noise of an individual device which is in an operable state but is not being fed a usable signal |
| Ohm | Unit of electrical resistance. In speaker construction, the (acoustic) impedance is indicated in ohms. |
| Onboard soundcard | Modern soundcards have their own data storage and processing units, which take some burden off their computer. Onboard soundcards are located directly on the motherboard. |
| On-ear headphones | Common headphone design. The receiver is placed directly on the ear, but does not completely cover the ear. |
| Optical cable | Used for the optical transmission of signals. The light signals are passed through a mixture of quartz and glass, known as optical fibers. |
| Over-ear headphones | Headphone construction. Like on-ear construction, however, covers the entire ear. |
| Passive Noise Canceling | A feature found on many new kinds of headphones whereby sound from the outside environment is filtered out by passive means such as padding or insulation. |
| Passive radiator | With no magnet or moving coil, these bass drivers save on space and power for smaller systems such as Bluetooth speakers while still providing an impressive level of bass performance. |
| Passive speaker | Typical passive speakers require the signal from an external amplifier for sound production. |
| Phase | The angle-like quantity of a wave, in our case a sound wave with 360° corresponding to a complete oscillation and 180° being half. |
| Phase plug | Replace the dust cap on some cone drivers: unlike dust caps (which are connected to the cone and therefore mobile), phase plugs are fixed. They present frequencies resulting from phase shifts between direct sound and reflected sound from being canceled out. Phase plugs made of copper or aluminum increase the thermal load capacity of a speaker: power loss from the voice coil is then dissipated into the air as heat. |
| Phone connector | A generic term for the kind of cable end on typical wired headphones and AUX cables. |
| Pickup | Indicates the front part of a record player needle, which is used to read sound signals stored on a record. |
| Power amplifier | A power amplifier is a Hi-Fi component that only encompasses the audio signal amplifier. |
| Pre-amplifier | A pre-amplifier is a Hi-Fi component that prepares audio signals from different sources for output to the power amplifier. |
| Pulse code modulation (PCM) | Pulse code modulation is a process for encoding analog signals into binary data. This makes it possible to digitalize all kinds of analog signals such as videos, speech, music, telemetry, or virtual reality. |
| Push terminals | Push terminals are an alternative to binding posts for fixing cables to a speaker, receiver, or amplifier. |
| Radiation angle | The radiation angle measures the size of the area in front of a speaker where the sound is directed, and thus sounds best |
| RCA connector | A type of connector cable used to carry audio and video signals, with audio often divided into left and right channels. Also called a phono connector. |
| Rear speaker | Rear speakers are the speakers in a typical 5.1 home cinema configuration that are used in the rear area starting from the listening position. They are often referred to as effect speakers or surround back. |
| Resilience | Describes a power value in watts that can be absorbed by a speaker. |
| Resonance frequency | The resonance frequency is the frequency at which the amplitude of an oscillating system is greater than that of the impulse of adjacent frequencies. |
| Reverberation | Reverberation is an acoustic phenomenon in room acoustics. Reverberation is caused by reflections of sound waves on surfaces. |
| Ripple pickup | This phenomenon can occur when connecting several devices and is usually audible as a humming noise. |
| Room acoustics | Room acoustics denotes the acoustic properties of a room. Important factors are reflection, absorption and diffusion of the sound. |
| Room modes | Term for superposition of sound waves. |
| SCART | SCART is a somewhat outdated standard for connectors between audio and video devices. |
| Silent disco | In a silent disco, visitors listen to the music via headphones. This allows events to take place where loud music is not allowed, for example in public spaces. |
| Sound card | Hardware for laptops and desktop computers to generate and output audio signals. |
| Sound emission | In acoustics, sound emission is defined as the output of sounds from a sound source. |
| Sound filter | Another name for an equaliser |
| Sound pressure level | The sound pressure level is a logarithmic parameter describing the strength of a sound source. |
| Source device | The device which plays the audio or video track in question. |
| SPDIF | Designation for an optical interface via which sound signals can be transmitted by means of fiber optic cables. Another designation is TOSLINK. |
| Sweet spot | The sweet spot refers to the (listening) position in a room where the sound of an audio system is at its absolute best. |
| Thiele/small parameters | A set of electromechanical parameters that define bass driver performance. |
| THX | Quality guidelines for cinema sound initiated by Hollywood director George Lucas (Star Wars) with the basic idea that film audio should sound equally good in every cinema. |
| TOSLINK | Designation for an optical interface via which sound signals can be transmitted by means of fiber optic cables. Another name is S/PDIF. |
| Transparency Mode | The opposite of active noise canceling on a set of headphones - outside sounds are amplified instead of being blended out. |
| Ultra HD BluRay | UHD or 4K resolution is a resolution standard that can display up to 3,840 x 2,160 pixels instead of the conventional Blu-ray, which can display "only" 1920 x 1080 pixels. |
| USB audio | Interface for the transmission of audio signals via USB. |
| USB port | The port of a universal serial bus, used for transmitting data or less commonly power |
| USB soundcard | Some speakers are built with a USB soundcard, meaning they can be connected directly to a computer's USB port and do not require any computing power from the computer. |
| Vector Linear Shaping Circuitry | A technology which checks incoming and outgoing signals for distorting sounds such as static and eliminates them. This makes the details easier to hear, which could otherwise be drowned out by high frequency static noise. |
| VESA | Abbreviation for "Video Electronics Standards Association". VESA is a standardized fitting for mounting flat screens, among other things, to walls |
| Wave field synthesis | Wave Field Synthesis (WFS) is an acoustic reproduction technology that generates virtual spatial sound environments through wave fronts. |
| Wide band speaker | A type of speaker where less drivers handle a wider part of the frequency range. |
| Wireless HDMI | Colloquial term for wireless transmission of HDMI signals. |
| XLR | Also known as Cannon plugs, XLR is an industry standard for electrical connectors in professional sound reinforcement and recording studio technology. |
| 2-way speaker | In this kind of speaker, two drivers (usually a tweeter and a woofer) split the frequency range to be reproduced. |
| 3-way speaker | A speaker that has separate drivers for high, medium and low frequencies. |