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 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.
Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an audio source privately, in contrast to a loudspeaker, which emits sound into the open air for anyone nearby to hear. Headphones are also known as earphones or, colloquially, cans. Circumaural and supra-aural headphones use a band over the top of the head to hold the speakers in place. Another type, known as earbuds or earpieces, consists of individual units that plug into the user's ear canal. A third type are bone conduction headphones, which typically wrap around the back of the head and rest in front of the ear canal, leaving the ear canal open. In the context of telecommunication, a headset is a combination of a headphone and microphone.
A DI unit is an electronic device typically used in recording studios and in sound reinforcement systems to connect a high output impedance unbalanced output signal to a low-impedance, microphone level, balanced input, usually via an XLR connector and XLR cable. DIs are frequently used to connect an electric guitar or electric bass to a mixing console's microphone input jack. The DI performs level matching, balancing, and either active buffering or passive impedance matching/impedance bridging. DI units are typically metal boxes with input and output jacks and, for more expensive units, “ground lift” and attenuator switches.
Bose Corporation is an American manufacturing company that predominantly sells audio equipment. The company was established by Amar Bose in 1964 and is based in Framingham, Massachusetts. It is best known for its home audio systems and speakers, noise cancelling headphones, professional audio products and automobile sound systems. Bose has a reputation for being particularly protective of its patents, trademarks, and brands.
A remaster is a change in the sound or image quality of previously created forms of media, whether audiophonic, cinematic, or videographic. The resulting product is said to be remastered. The terms digital remastering and digitally remastered are also used.
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.
JBL is an American audio equipment manufacturer headquartered in Los Angeles, California, United States. JBL serves the customer home and professional market. The professional market includes studios, installed/tour/portable sound, music production, DJ, cinema markets. The home market includes high-end home amplification/speakers/headphones as well as high-end car audio. JBL is owned by Harman International, itself a subsidiary of Samsung Electronics.
PS Audio is an American company specializing in high-fidelity audio components equipment for audiophiles and the sound recording industry. It currently produces audio amplifiers, preamplifiers, power related products, digital-to-analog converters, streaming audio, music management software and cables.
Shure Incorporated is an audio products corporation headquartered in the USA. It was founded by Sidney N. Shure in Chicago, Illinois, in 1925 as a supplier of radio parts kits. The company became a consumer and professional audio-electronics manufacturer of microphones, wireless microphone systems, phonograph cartridges, discussion systems, mixers, and digital signal processing. The company also manufactures listening products, including headphones, high-end earphones, and personal monitor systems.
Grado Labs is an American audio manufacturer known for hand building high-end dynamic open-back headphones and cartridges in Brooklyn, New York.
Milton Tasker "Bill" Putnam was an American audio engineer, songwriter, producer, studio designer and businessman, who has been described as "the father of modern recording". He was the inventor of the modern recording console and is recognised as a key figure in the development of the postwar commercial recording industry.
Ultimate Ears is an American custom in-ear monitor (IEM), speaker, and earphone manufacturer based in Irvine and Newark, California, United States.
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.
David Hafler was an American audio engineer. He was best known for his work on an improved version of the Williamson amplifier using the ultra-linear circuit of Alan Blumlein.
Delay is an audio signal processing technique that records an input signal to a storage medium and then plays it back after a period of time. When the delayed playback is mixed with the live audio, it creates an echo-like effect, whereby the original audio is heard followed by the delayed audio. The delayed signal may be played back multiple times, or fed back into the recording, to create the sound of a repeating, decaying echo.
Studio monitors are loudspeakers in speaker enclosures specifically designed for professional audio production applications, such as recording studios, filmmaking, television studios, radio studios and project or home studios, where accurate audio reproduction is crucial. Among audio engineers, the term monitor implies that the speaker is designed to produce relatively flat (linear) phase and frequency responses. In other words, it exhibits minimal emphasis or de-emphasis of particular frequencies, the loudspeaker gives an accurate reproduction of the tonal qualities of the source audio, and there will be no relative phase shift of particular frequencies—meaning no distortion in sound-stage perspective for stereo recordings. Beyond stereo sound-stage requirements, a linear phase response helps impulse response remain true to source without encountering "smearing". An unqualified reference to a monitor often refers to a near-field design. This is a speaker small enough to sit on a stand or desk in proximity to the listener, so that most of the sound that the listener hears is coming directly from the speaker, rather than reflecting off walls and ceilings. Monitor speakers may include more than one type of driver or, for monitoring low-frequency sounds, such as bass drum, additional subwoofer cabinets may be used.
Bill Dudleston is the president and founder of Legacy Audio, a high-end audio and home theater equipment manufacturer located in Springfield, Illinois, United States. As a member of the Audio Engineering Society and the American Institute of Chemical Engineers, Dudleston has been inducted into a regional Hall of Fame and is also listed in Who's Who of American Businessmen.
An audio engineer helps to produce a recording or a live performance, balancing and adjusting sound sources using equalization, dynamics processing and audio effects, mixing, reproduction, and reinforcement of sound. Audio engineers work on the "technical aspect of recording—the placing of microphones, pre-amp knobs, the setting of levels. The physical recording of any project is done by an engineer… the nuts and bolts."
Masters of Scale is a business podcast and media brand owned and produced by WaitWhat, the media company founded and led by former TED executives June Cohen and Deron Triff. In 2017, Masters of Scale launched as a business and leadership podcast hosted by Reid Hoffman, the co-founder of LinkedIn and partner at Greylock Partners. Masters of Scale aims to “democratize entrepreneurship” and has since extended into multiple podcasts, a learning app, a book., and events, including the Masters of Scale Summit.
