In an amplifier, a presence control boosts the upper mid-range frequencies to make the sounds of voices and instruments with similar tonal ranges seem more "present". [1]
On television production studio's sound desk, there can be several presence controls, for several different, switchable, frequencies. [2] There is a limit to the flexibility of such controls, and they are sometimes insufficient. If the degree of mis-match between microphones is great, simply increasing presence is not enough, and instead a sound engineer will use a graphic equalizer, sometimes several, each connected to an individual sound channel. [3]
Presence controls can also be found on electric guitar amplifiers. The first presence control on a Fender amplifier, for example, appeared in 1954 on the Twin. In 1955 it appeared on the 1/15 Pro-Amp, the 3/10 Bandmaster, the 2/10 Super, [4] and the 4/10 Bassman. [5] The original Fender presence control acted upon the amplifier's negative-feedback loop. As the level of "presence" was increased, so more and more of the higher frequencies in the negative-feedback loop were dumped to ground, leaving the low and mid-range frequencies. Increasing the presence resulted in there being less and less negative feedback on high frequencies. The effect varied according to amplitude. [6]
Later Fender amplifiers used a different presence control. The presence control on the 1975 Fender Super Twin did not modify the negative feedback loop, but was an active equalization circuit, controlling the 3.9 kHz frequency range. It had the ability to both amplify (boost) and attenuate (cut), unlike the earlier presence control. [6]
In a 3-way loudspeaker system, with tweeter, woofer, and mid-range speaker, a presence control is simply a volume control for the mid-range speaker. [7]
An effects unit or effects pedal is an electronic device that alters the sound of a musical instrument or other audio source through audio signal processing.
An audio power amplifier is an electronic amplifier that amplifies low-power electronic audio signals such as the signal from radio receiver or electric guitar pickup to a level that is high enough for driving loudspeakers or headphones. Audio power amplifiers are found in all manner of sound systems including sound reinforcement, public address and home audio systems and musical instrument amplifiers like guitar amplifiers. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers.
An instrument amplifier is an electronic device that converts the often barely audible or purely electronic signal of a musical instrument into a larger electronic signal to feed to a loudspeaker. An instrument amplifier is used with musical instruments such as an electric guitar, an electric bass, electric organ, synthesizers and drum machine to convert the signal from the pickup or other sound source into an electronic signal that has enough power, due to being routed through a power amplifier, capable of driving one or more loudspeaker that can be heard by the performers and audience.
A guitar amplifier is an electronic device or system that strengthens the weak electrical signal from a pickup on an electric guitar, bass guitar, or acoustic guitar so that it can produce sound through one or more loudspeakers, which are typically housed in a wooden cabinet. A guitar amplifier may be a standalone wood or metal cabinet that contains only the power amplifier circuits, requiring the use of a separate speaker cabinet–or it may be a "combo" amplifier, which contains both the amplifier and one or more speakers in a wooden cabinet. There is a wide range of sizes and power ratings for guitar amplifiers, from small, lightweight "practice amplifiers" with a single 6" speaker and a 10 watt amp to heavy combo amps with four 10” or four 12" speakers and a powerful 100 watt amplifier, which are loud enough to use in a nightclub or bar performance.
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.
Marshall Amplification is a British company that designs and manufactures music amplifiers, speaker cabinets, brands personal headphones and earphones, a record label and, having acquired Natal Drums, drums and bongos. It was founded by drum shop owner and drummer Jim Marshall, and is now based in Bletchley, Milton Keynes, Buckinghamshire.
Fender amplifiers are a series of electric instrument amplifiers renowned by musicians worldwide. The Fender Musical Instruments Corporation has continuously manufactured guitar amplifiers since their foundation, Leo Fender began building guitar amplifiers before he started manufacturing electric guitars. The first of these were the K&F models, produced between 1945 and 1946. Fender amplifiers would become favourites of many famous guitarists such as Stevie Ray Vaughan, Jimi Hendrix and Eric Clapton, helping them pioneer their sounds.
Dumble is a guitar amplifier manufacturer in Los Angeles, California.
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 Vox AC30 is a guitar amplifier manufactured by Vox. It was introduced in 1958 to meet the growing demand for louder amplifiers. Characterised by its "jangly" high-end sound it has become widely recognized by British musicians and others.
A bass amplifier or "bass amp" is a musical instrument electronic device that uses electrical power to make lower-pitched instruments such as the bass guitar or double bass loud enough to be heard by the performers and audience. Bass amps typically consist of a preamplifier, tone controls, a power amplifier and one or more loudspeakers ("drivers") in a cabinet.
Distortion and overdrive are forms of audio signal processing used to alter the sound of amplified electric musical instruments, usually by increasing their gain, producing a "fuzzy", "growling", or "gritty" tone. Distortion is most commonly used with the electric guitar, but may also be used with other electric instruments such as electric bass, electric piano, and Hammond organ. Guitarists playing electric blues originally obtained an overdriven sound by turning up their vacuum tube-powered guitar amplifiers to high volumes, which caused the signal to distort. While overdriven tube amps are still used to obtain overdrive, especially in genres like blues and rockabilly, a number of other ways to produce distortion have been developed since the 1960s, such as distortion effect pedals. The growling tone of a distorted electric guitar is a key part of many genres, including blues and many rock music genres, notably hard rock, punk rock, hardcore punk, acid rock, and heavy metal music, while the use of distorted bass has been essential in a genre of hip hop music and alternative hip hop known as "SoundCloud rap".
The Fender Prosonic guitar amplifier was produced by Fender Musical Instruments from 1996 to 2002. Available in head and combo versions, the Prosonic featured several departures in design from traditional Fender amplifiers such as the Bassman, Twin Reverb, and Deluxe Reverb. Designed by Bruce Zinky as a project for the Fender Custom Shop, the amplifier later had a non-Custom Shop production run at the Fender facilities in Corona, California. It was initially priced to compete with buyers in the so-called boutique amplifier market who were seeking more distortion than any previous Fender had ever offered. It is believed that high list prices, and deviations from established Fender amplifier designs, swayed many buyers away from the Prosonic. It developed a cult following among serious guitarists, aided by the rise of musician-centric Internet communities.
The Fender Twin and Twin Reverb are guitar amplifiers made by Fender Musical Instruments Corporation. The Twin was introduced in 1952, two years before Fender began selling Stratocaster electric guitars. The amps are known for their characteristically clean tone.
The Fender Bassman is a bass amplifier series introduced by Fender during 1952. Initially intended to amplify bass guitars, the 5B6 Bassman was used by musicians for other instrument amplification, including the electric guitar, harmonica, and pedal steel guitars. Besides being a popular and important amplifier in its own right, the Bassman also became the foundation on which Marshall and other companies built their high-gain tube amplifiers.
The Fender Super was a guitar amplifier made by Fender between 1947 and 1963 and, as the Super Reverb, until 1981. Though it was designed for a clean sound, its overdriven sound is praised by players and critics.
The Mesa Boogie Mark Series is a series of guitar amplifier made by Mesa Engineering. Originally just referred to as "Boogies," the product line took on the moniker "Mark Series" as newer revisions were put into production. The Mark Series amplifier was Mesa's flagship product until the introduction of the Rectifier series, and the amplifiers are collectable.
A stage monitor system is a set of performer-facing loudspeakers called monitor speakers, stage monitors, floor monitors, wedges, or foldbacks on stage during live music performances in which a sound reinforcement system is used to amplify a performance for the audience. The monitor system allows musicians to hear themselves and fellow band members clearly.
The Marshall JTM45 is the first guitar amplifier made by Marshall. First produced in 1963, it has been called a "seminal" amplifier, and is praised as the most desirable of all the company's amplifiers.
Equalization in sound recording and reproduction is the process of adjusting the volume of different frequency bands within an audio signal. The circuit or equipment used to achieve this is called an equalizer.