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 subwoofer is a loudspeaker designed to reproduce low-pitched audio frequencies, known as bass and sub-bass, that are lower in frequency than those which can be (optimally) generated by a woofer. The typical frequency range that is covered by a subwoofer is about 20–200 Hz for consumer products, below 100 Hz for professional live sound, and below 80 Hz in THX-certified systems. Thus, one or more subwoofers are important for high-quality sound reproduction as they are responsible for the lowest two to three octaves of the ten octaves that are audible. This very low-frequency (VLF) range reproduces the natural fundamental tones of the bass drum, electric bass, double bass, grand piano, contrabassoon, tuba, in addition to thunder, gunshots, explosions, etc.
A loudspeaker is a combination of one or more speaker drivers, an enclosure, and electrical connections. The speaker driver is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound.
Binaural recording is a method of recording sound that uses two microphones, arranged with the intent to create a 3D stereo sound sensation for the listener of actually being in the room with the performers or instruments. This effect is often created using a technique known as dummy head recording, wherein a mannequin head is fitted with a microphone in each ear. Binaural recording is intended for replay using headphones and will not translate properly over stereo speakers. This idea of a three-dimensional or "internal" form of sound has also translated into useful advancement of technology in many things such as stethoscopes creating "in-head" acoustics and IMAX movies being able to create a three-dimensional acoustic experience.
An audiophile is a person who is enthusiastic about high-fidelity sound reproduction. The audiophile seeks to achieve high sound quality in the audio reproduction of recorded music, typically in a quiet listening space in a room with good acoustics.
A home cinema, also called a home theater or theater room, is a home entertainment audio-visual system that seeks to reproduce a movie theater experience and mood using consumer electronics-grade video and audio equipment and is set up in a room or backyard of a private home. Some studies show that films are rated better and generate more intense emotions when watched in a movie theater, but convenience is a major appeal for home cinemas. In the 1980s, home cinemas typically consisted of a movie pre-recorded on a LaserDisc or VHS tape; a LaserDisc Player or VCR; and a heavy, bulky large-screen cathode-ray tube TV set, although sometimes CRT projectors were used instead. In the 2000s, technological innovations in sound systems, video player equipment, TV screens and video projectors have changed the equipment used in home cinema set-ups and enabled home users to experience a higher-resolution screen image, improved sound quality and components that offer users more options. The development of Internet-based subscription services means that 2020s-era home theatre users do not have to commute to a video rental store as was common in the 1980s and 1990s.
Surround sound is a technique for enriching the fidelity and depth of sound reproduction by using multiple audio channels from speakers that surround the listener. Its first application was in movie theaters. Prior to surround sound, theater sound systems commonly had three screen channels of sound that played from three loudspeakers located in front of the audience. Surround sound adds one or more channels from loudspeakers to the side or behind the listener that are able to create the sensation of sound coming from any horizontal direction around the listener.
Mastering, a form of audio post production, is the process of preparing and transferring recorded audio from a source containing the final mix to a data storage device, the source from which all copies will be produced. In recent years, digital masters have become usual, although analog masters—such as audio tapes—are still being used by the manufacturing industry, particularly by a few engineers who specialize in analog mastering.
Dolby Laboratories, Inc. is a British-American technology corporation specializing in audio noise reduction, audio encoding/compression, spatial audio, and HDR imaging. Dolby licenses its technologies to consumer electronics manufacturers.
A sound reinforcement system is the combination of microphones, signal processors, amplifiers, and loudspeakers in enclosures all controlled by a mixing console that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience. In many situations, a sound reinforcement system is also used to enhance or alter the sound of the sources on the stage, typically by using electronic effects, such as reverb, as opposed to simply amplifying the sources unaltered.
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.
Klipsch Audio Technologies is an American loudspeaker company based in Indianapolis, Indiana. Founded in Hope, Arkansas, in 1946 as 'Klipsch and Associates' by Paul W. Klipsch, the company produces loudspeaker drivers and enclosures, as well as complete loudspeakers for high-end, high-fidelity sound systems, public address applications, and personal computers.
10.2 is the surround sound format developed by THX creator Tomlinson Holman of TMH Labs and the University of Southern California. Developed along with Chris Kyriakakis of the USC Viterbi School of Engineering, 10.2 refers to the format's slogan: "Twice as good as 5.1". However, there actually may be 14 discrete channels if the left and right point surround channels are included. He states that 5.1, a name which he himself came up with in 1987 was chosen as it was "the minimum number of channels necessary to give a sense of spaciousness". Holman and others state that higher sampling rates, which is a recent trend in digital recording, does not have a significant perceivable effect and that the next frontier in sound engineering is to increase the number of discrete channels to meet human spatial sound perception. As of 2015, several decoding, UHD, or virtual expansion processors have approached numbers as great or greater than 10.2.
Digital room correction is a process in the field of acoustics where digital filters designed to ameliorate unfavorable effects of a room's acoustics are applied to the input of a sound reproduction system. Modern room correction systems produce substantial improvements in the time domain and frequency domain response of the sound reproduction system.
Wave field synthesis (WFS) is a spatial audio rendering technique, characterized by creation of virtual acoustic environments. It produces artificial wavefronts synthesized by a large number of individually driven loudspeakers from elementary waves. Such wavefronts seem to originate from a virtual starting point, the virtual sound source. Contrary to traditional phantom sound sources, the localization of WFS established virtual sound sources does not depend on the listener's position. Like as a genuine sound source the virtual source remains at fixed starting point.
Loudspeaker measurement is the practice of determining the behaviour of loudspeakers by measuring various aspects of performance. This measurement is especially important because loudspeakers, being transducers, have a higher level of distortion than other audio system components used in playback or sound reinforcement.
Lexicon is an American company that engineers, manufactures, and markets audio equipment as a brand of Harman International Industries. The company was founded in 1971 with headquarters in Waltham, Massachusetts, and offices in Salt Lake City, Utah. It was acquired by Harman in 1993.
Loudness compensation, or simply loudness, is a setting found on some hi-fi equipment that increases the level of the high and low frequencies. This is intended to be used while listening at low-volume levels, to compensate for the fact that as the loudness of audio decreases, the ear's lower sensitivity to extreme high and low frequencies may cause these signals to fall below the threshold of hearing. As a result audio material may become thin sounding at low volumes, losing bass and treble. The loudness compensation feature applies equalization and is intended to rectify this situation.
Edgar Marion Villchur was an American inventor, educator, and writer widely known for his 1954 invention of the acoustic suspension loudspeaker which revolutionized the field of high-fidelity equipment. A speaker Villchur developed, the AR-3, is exhibited at The Smithsonian Institution's Information Age Exhibit in Washington, DC.
Chris Kyriakakis is a professor of electrical engineering, author, and inventor of audio technologies. He is the co-inventor of the Audyssey MultEQ digital room correction system. In 2004 he co-founded Audyssey Laboratories.
