High fidelity is the high-quality reproduction of sound. It is popular with audiophiles and home audio enthusiasts. Ideally, high-fidelity equipment has inaudible noise and distortion, and a flat frequency response within the human hearing range.
A loudspeaker is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound. A speaker system, also often simply referred to as a "speaker" or "loudspeaker", comprises one or more such speaker drivers, an enclosure, and electrical connections possibly including a crossover network. The speaker driver can be viewed as a linear motor attached to a diaphragm which couples that motor's movement to motion of air, that is, sound. An audio signal, typically from a microphone, recording, or radio broadcast, is amplified electronically to a power level capable of driving that motor in order to reproduce the sound corresponding to the original unamplified electronic signal. This is thus the opposite function to the microphone; indeed the dynamic speaker driver, by far the most common type, is a linear motor in the same basic configuration as the dynamic microphone which uses such a motor in reverse, as a generator.
Audio crossovers are a type of electronic filter circuitry that splits an audio signal into two or more frequency ranges, so that the signals can be sent to loudspeaker drivers that are designed to operate within different frequency ranges. The crossover filters can be either active or passive. They are often described as two-way or three-way, which indicate, respectively, that the crossover splits a given signal into two frequency ranges or three frequency ranges. Crossovers are used in loudspeaker cabinets, power amplifiers in consumer electronics and pro audio and musical instrument amplifier products. For the latter two markets, crossovers are used in bass amplifiers, keyboard amplifiers, bass and keyboard speaker enclosures and sound reinforcement system equipment.
An audiophile is a person who is enthusiastic about high-fidelity sound reproduction. An audiophile seeks to reproduce the sound of a piece of recorded music or a live musical performance, typically inside closed headphones, In-ear monitors, open headphones in a quiet listening space, or a room with good acoustics.
A woofer or bass speaker is a technical term for a loudspeaker driver designed to produce low frequency sounds, typically from 50 Hz up to 1000 Hz. The name is from the onomatopoeic English word for a dog's bark, "woof". The most common design for a woofer is the electrodynamic driver, which typically uses a stiff paper cone, driven by a voice coil surrounded by a magnetic field.
Audio power is the electrical power transferred from an audio amplifier to a loudspeaker, measured in watts. The electrical power delivered to the loudspeaker, together with its efficiency, determines the sound power generated.
In an audio system, the damping factor gives the ratio of the rated impedance of the loudspeaker to the source impedance. Only the magnitude of the loudspeaker impedance is used, and the amplifier output impedance is assumed to be totally resistive.
A horn loudspeaker is a loudspeaker or loudspeaker element which uses an acoustic horn to increase the overall efficiency of the driving element(s). A common form (right) consists of a compression driver which produces sound waves with a small metal diaphragm vibrated by an electromagnet, attached to a horn, a flaring duct to conduct the sound waves to the open air. Another type is a woofer driver mounted in a loudspeaker enclosure which is divided by internal partitions to form a zigzag flaring duct which functions as a horn; this type is called a folded horn speaker. The horn serves to improve the coupling efficiency between the speaker driver and the air. The horn can be thought of as an "acoustic transformer" that provides impedance matching between the relatively dense diaphragm material and the less-dense air. The result is greater acoustic output power from a given driver.
A headphone amplifier is a low-powered audio amplifier designed particularly to drive headphones worn on or in the ears, instead of loudspeakers in speaker enclosures. Most commonly, headphone amplifiers are found embedded in electronic devices that have a headphone jack, such as integrated amplifiers, portable music players, and televisions. However, standalone units are used, especially in audiophile markets and in professional audio applications, such as music studios. Headphone amplifiers are available in consumer-grade models used by hi-fi enthusiasts and audiophiles and professional audio models, which are used in recording studios.
Powered speakers, also known as self-powered speakers and active speakers, are loudspeakers that have built-in amplifiers. Powered speakers are used in a range of settings, including in sound reinforcement systems, both for the main speakers facing the audience and the monitor speakers facing the performers; by DJs performing at dance events and raves; in private homes as part of hi-fi or home cinema audio systems and as computer speakers. They can be connected directly to a mixing console or other low-level audio signal source without the need for an external amplifier. Some active speakers designed for sound reinforcement system use have an onboard mixing console and microphone preamplifier, which enables microphones to be connected directly to the speaker.
The chief electrical characteristic of a dynamic loudspeaker's driver is its electrical impedance as a function of frequency. It can be visualized by plotting it as a graph, called the impedance curve.
Bi-amping and tri-amping is the practice of using two or three audio amplifiers to amplify different audio frequency ranges, with the amplified signals being routed to different speaker drivers, such as woofers, subwoofers and tweeters. Biamping can be done with a single power amplifier if the device has more than one amplifier, as the case with a stereo power amp. Triamping cannot be done with a stereo power amp; a mono power amp would need to be added or a home theatre receiver could be used. With bi-amping and tri-amping, an audio crossover is used to divide a sound signal into different frequency ranges, each of which is then separately amplified and routed to separate loudspeaker drivers. In some bass amplifiers using bi-amping, the woofer and horn-loaded tweeter are in the same speaker enclosure. In some bi-amp set-ups, the drivers are in separate speaker enclosures, such as with home stereos that contain two speakers and a separate subwoofer.
KEF is a British company specialising in the design and production of a range of high-end audio products, including HiFi speakers, subwoofers, architecture speakers, wireless speakers, and headphones. It was founded in Maidstone, Kent in 1961 by a BBC engineer Raymond Cooke OBE (1925–1995).
Tube sound is the characteristic sound associated with a vacuum tube amplifier, a vacuum tube-based audio amplifier. At first, the concept of tube sound did not exist, because practically all electronic amplification of audio signals was done with vacuum tubes and other comparable methods were not known or used. After introduction of solid state amplifiers, tube sound appeared as the logical complement of transistor sound, which had some negative connotations due to crossover distortion in early transistor amplifiers. However, solid state amplifiers have been developed to be flawless and the sound is later regarded neutral compared to tube amplifiers. Thus the tube sound now means 'euphonic distortion.' The audible significance of tube amplification on audio signals is a subject of continuing debate among audio enthusiasts.
The Naim NAIT is an integrated amplifier from the British hi-fi manufacturer, Naim Audio. The original NAIT is one of the most recognisable pieces of hi-fi equipment ever made. Hi-fi critic Lucio Cadeddu recognised its legendary status, referring to it as "one of the most controversial and famous integrated amps in the history of HiFi".
Naim Audio is a specialist British manufacturer of high-end audio amplifiers well known for their self described qualities of "pace, rhythm and timing".
The NAD 3020 is a stereo integrated amplifier by NAD Electronics, considered to be one of the most important components in the history of high fidelity audio. Launched in 1978, this highly affordable product delivered a good quality sound, which acquired a reputation as an audiophile amplifier of exceptional value. By 1998, the NAD 3020 had become the most well known and best-selling audio amplifier in history.
The Linn Isobarik, nicknamed "Bariks" or "Briks", is a loudspeaker designed and manufactured by Linn Products. The Isobarik is known for both its reproduction of low bass frequencies and being very demanding on amplifiers.
The LS3/5A is a small studio monitor loudspeaker originated by the BBC for use by outside broadcast vans to ensure quality of their broadcasts. The speaker concept set out transparent and natural sound as the goal, and the achievement of the end result is widely acknowledged.
The Quad Electrostatic Loudspeaker (ESL) is the world's first production full-range electrostatic loudspeaker, launched in 1957 by Quad Electroacoustics, then known as the Acoustical Manufacturing Co. Ltd. The speaker is shaped somewhat like a home electric radiator curved slightly on the vertical axis. They are widely admired for their clarity and precision, but known to be difficult speakers to run and maintain.
