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Re-amping is a process often used in multitrack recording in which a recorded signal is routed back out of the editing environment and run through external processing using effects units and then into a guitar amplifier and a guitar speaker cabinet or a reverb chamber. Originally, the technique was used mostly for electric guitars: it facilitates a separation of guitar playing from guitar amplifier processing—a previously recorded audio program is played back and re-recorded at a later time for the purpose of adding effects, ambiance such as reverb or echo, and the tone shaping imbued by certain amps and cabinets. The technique has since evolved over the 2000s to include many other applications. Re-amping can also be applied to other instruments and program, such as recorded drums, synthesizers, and virtual instruments.
Examples of common re-amping objectives include taking a pre-recorded electric guitar track and adding musically pleasing amplifier distortion/overdrive, room tone such as reverb, audio compression, EQ/filters, envelope followers, resonance, and gating. Re-amping is often used to "warm up" dry tracks, which often means adding complex, musically interesting effects. By playing a dry signal through a studio's main monitors and then using room mics to capture the ambiance, engineers are able to create realistic reverbs and blend the "wet" (modified) signal with the original dry recorded sound to achieve the desired amount of depth.
The technique is especially useful for "softening" stereo drum tracks. By pointing the monitors away from each other and miking each speaker individually, the stereo image can be well preserved and a new sense of "depth" can be added to the track. It is important for audio engineers to check that the microphones being used are in phase to avoid problems with the mix.
An electric guitarist records a dry, unprocessed, unaffected track in a recording studio. This is often achieved by connecting the guitar into a DI unit (a Direct Input or Direct Inject buffer box) that is fed to a recording console or, alternatively, bypassing the console by using an outboard preamplifier. Often, the guitarist's signal is sent to both recorder and guitar amp simultaneously, providing the guitarist with a proper amplifier "feel" while they are playing while also tracking (recording) a dry (un-effects processed) signal.
Later, the dry, direct, unprocessed guitar recording is fed to a bridging device (a Reamp unit or reverse DI box) to "re-record" the guitarist's unprocessed performance through a dedicated guitar amplifier cabinet and/or external effects units. The guitar amplifier is placed in the live room or isolation booth of the recording studio and is set up to produce the desired tonal quality, including distortion character and room reverberation. A microphone is placed near the guitar speaker and a new track is recorded, producing the re-amplified, processed track. The microphone cable is connected to the mixing console or mic preamp using a cable, as usual, without using a bridging device.
External effects such as stomp boxes and guitar multi-fx processors can also be included in the re-amping process. As well as physical devices that require an impedance-matched guitar pickup signal, software-based virtual guitar effects and amps can be included in the re-amping process.
Re-amping allows guitarists and other electronic musicians to record their tracks and go home, leaving the engineer and producer to spend more time dialing in "just right" settings and effects on prerecorded tracks. When re-amping electric guitar tracks, the guitarist need not be present for the engineer to experiment with a range of effects, mic positions, speaker cabinets, amplifiers, effects pedals, and overall tonality – continuously replaying the prerecorded tracks while experimenting with new settings and tones. When a desired tone is finally achieved, the guitarist's dry performance is re-recorded, or "re-amped," with all added effects.
Manufacturers of instrument processing gear such as guitar effects, or equipment reviewers, can gather a library of dry performance tracks, performed and edited well, and then run these ideal tracks through the processing gear to demonstrate the sounds that the processing gear can produce. An unlimited number of performance playback passes, including looping, enables trying out many combinations of settings quickly, including microphone techniques. When guitar amp or amp simulator designers try various circuit component values or settings, they can use the dry tracks as prepared, always available input test signals, and consistent reference signals.
Another advantage of re-amping is that it enables producers and band members to have more options for remixing and redoing a recording a long time after the original recording. If the original recording of a song with electric guitar is done in 1985, and the electric guitarist's sound was only recorded with a mic in front of her/his combo amp or speaker cabinet, the recording will lock in the specific type of distortion, reverb, flanger processing and other effects that were used, which might sound "dated" several decades later. A producer who is tasked with doing a remix of this song 30 years later cannot "undo" or remove the distortion, reverb, chorus or flanger effects, and so there are limited options for remixing the guitar sound. On the other hand, if the engineering and production team in 1985 had simultaneously tracked (recorded) a "dry", DI out signal from the electric guitar's pickups, a producer remixing the song 30 years later could take the dry guitar signal and re-amp it through 2000s-era digital effects and speaker systems, giving a new sound to this 1985 track.
Direct inject (DI) is a device for connecting an unbalanced, high-impedance, low-level signal (commonly a guitar pickup's signal) into audio equipment designed for a low-impedance balanced signal (such as a DAW) or audio consoles. Reverse-DI means running this same device or technique in reverse – connecting a high-level (typically balanced, low-impedance) signal into audio equipment that was designed for low-level, unbalanced, high-impedance signals, such as a guitar amplifier.
Playing back a signal from recording studio equipment directly into a guitar amplifier can cause unwanted side-effects such as input-stage distortion, treble loss or overemphasis, and ground-loop hum; thus there is sometimes a need for impedance conversion, level-matching, and ground alteration. Like running a guitar signal through a guitar effects pedal that is set to Bypass, re-amping introduces some degree of sonic degradation compared to playing a guitar live directly into a guitar amp rig.
A re-amping device commonly employs a reversed Direct Inject (DI) transformer with some resistors added for level and impedance shift. Level and impedance adjustment can be achieved by adding a potentiometer or adjustable resistor. A proper re-amping device converts a balanced signal to an unbalanced signal, reduces a high studio-level (line-level) signal down to a low guitar-level signal, and shifts the output to a high instrument-level impedance (typically a guitar pickup impedance).
In conventional re-amplification, a dry recorded signal is sent into a balanced XLR input. An unbalanced ¼" (Tip-Sleeve) phone connector is typically used for the output, which is connected to the guitar amp rig. Some re-amping devices offer a pad (attenuator) switch to reduce a too-hot output level. Sometimes a guitar volume pedal or buffered effects pedal can work adequately for re-amping, depending on grounding, levels, and impedance. Another approach to simulating the high impedance of a guitar pickup is to use a passive DI and add a 10 K-ohm resistor in series with the signal connection inside a 1/4" plug.
While "reverse DI" re-recording techniques have been used for decades, the process was popularized in part by the introduction of the Reamp device in 1993. The registered trademark "Reamp" describes a patented invention ( U.S. patent 6,005,950 ) filed in 1994 by audio engineer John Cuniberti, perhaps best known for his lifelong engineering work with guitarist Joe Satriani. The Reamp inductively couples balanced line-level sources into unbalanced guitar-level destinations (e.g., DAW output to guitar amp input) and includes a potentiometer that alters both signal level and source impedance. Derivations of the Reamp trademark, such as "reamping" and "re-amplification," have become common terminology in professional audio to describe the process of amplified re-recording – much like the word "Band-aid" is often used to describe adhesive bandages (see Genericized trademark).
The process of re-recording has been used throughout the history of recording studios. Pierre Schaeffer in the 1930s and 1940s used recorded sounds, such as trains, and played them back with ambient alteration, re-recording the net result. Karlheinz Stockhausen and Edgard Varèse later used similar techniques. [1] Les Paul and Mary Ford recorded layered vocal harmonies and guitar parts, modifying prior tracks with effects such as ambient reverb while recording the net result together on a new track. Les Paul placed a loudspeaker at one end of a tunnel and a microphone at the other end. The loudspeaker played back previously recorded material - the microphone recorded the resulting altered sound.
Roger Nichols claims to have used a guitar re-recording process (not reverse DI) in 1968, partly to spread the stress on cranked tube amps across multiple amps, one at a time. A sound would be dialed in for several hours on one cranked guitar amplifier, and if this stress audibly wore down the amplifier components, another amplifier would be used to record the remaining work. It has been noted that Phil Spector, re-mixing the original Beatles’ Let It Be master tapes in 1970, may have re-recorded dry electric guitar program through a guitar amplifier.
Film sound re-recording is a time-honored practice. Sound designer Walter Murch is known for a technique called "worldizing" in which "real world" ambiance is added, via re-recording, to dry recorded program. Sound designer Nick Peck describes the worldizing process: "Place a speaker in a room or location with the desired aural fingerprint and position a microphone some distance from the speaker. Next, play back your original sounds through the speaker and re-record them on another recorder, capturing the sound with all the reverberant characteristics of the space. This requires much time and effort, but when only the most authentic reproduction will do, worldizing can get you there." [2]
Radial and Millennia Media products use the Reamp patent, or a variant of the patent, under license. The Reamp Company acknowledges that words such as "reamping" have become generic/colloquial audio expressions, but asserts that the word Reamp remains their legally registered trademark. In late 2010 Recording engineer John Cuniberti announced the sale of his Reamp patent, trademark and all business assets to Vancouver, Canada-based Radial Engineering Ltd., a leading manufacturer of products used by audio professionals and musicians around the world. [3]
An effects unit, effects processor, 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 amplifies low-power electronic audio signals, such as the signal from a radio receiver or an 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, 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.
A recording studio is a specialized facility for recording and mixing of instrumental or vocal musical performances, spoken words, and other sounds. They range in size from a small in-home project studio large enough to record a single singer-guitarist, to a large building with space for a full orchestra of 100 or more musicians. Ideally, both the recording and monitoring spaces are specially designed by an acoustician or audio engineer to achieve optimum acoustic properties.
An instrument amplifier is an electronic amplifier 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, electric piano, synthesizers and drum machine to convert the signal from the pickup or other sound source into an electronic signal that has enough power, produced by a power amplifier, to drive 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 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-inch speaker and a 10-watt amp to heavy combo amps with four 10-inch or four 12-inch speakers and a 100-watt amplifier, which are loud enough to use in a nightclub or bar performance.
A valve amplifier or tube amplifier is a type of electronic amplifier that uses vacuum tubes to increase the amplitude or power of a signal. Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers in the 1960s and 1970s. Valve amplifiers can be used for applications such as guitar amplifiers, satellite transponders such as DirecTV and GPS, high quality stereo amplifiers, military applications and very high power radio and UHF television transmitters.
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.
In audio engineering and sound recording, a high impedance bridging, voltage bridging, or simply bridging connection is one in which the load impedance is much larger than the source impedance. The load measures the source's voltage while minimally drawing current or affecting it.
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.
Scholz Research & Development, Inc. was the name of the company founded by musician and engineer Tom Scholz to design and manufacture music technology products.
Line 6 is a musical instrument and audio equipment manufacturer, best known as a pioneer in guitar amplifier and effect modeling. The company's products include guitar effects, modeling guitar amplifiers, software, electric guitars, and wireless systems. Line 6 has an active user community, and provides software that allows users to easily download and share patches or device settings for many of the company's products. Founded in 1996 and headquartered in Calabasas, California, the company has been a subsidiary of Yamaha Corporation since 2014.
A bass amplifier 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, synthesizer 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, grunge 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".
A guitar speaker is a loudspeaker – specifically the driver (transducer) part – designed for use in a combination guitar amplifier of an electric guitar, or for use in a guitar speaker cabinet. Typically these drivers produce only the frequency range relevant to electric guitars, which is similar to a regular woofer type driver, which is approximately 75 Hz — 5 kHz, or for electric bass speakers, down to 41 Hz for regular four-string basses or down to about 30 Hz for five-string instruments.
Live sound mixing is the blending of multiple sound sources by an audio engineer using a mixing console or software. Sounds that are mixed include those from instruments and voices which are picked up by microphones and pre-recorded material, such as songs on CD or a digital audio player. Individual sources are typically equalised to adjust the bass and treble response and routed to effect processors to ultimately be amplified and reproduced via a loudspeaker system. The live sound engineer listens and balances the various audio sources in a way that best suits the needs of the event.
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.
Fryette Amplification of North Hollywood, California is a manufacturer of hand-built electric guitar amplifiers, speaker cabinets, power amplifiers, sound effects pedals and pedalboard accessories. The company was founded as VHT Amplification in Studio City, Los Angeles, California by Steven Fryette in January 1989 and was the first to produce a true three-channel vacuum tube amplifier.
Record is a music software program developed by Swedish software developers Propellerhead Software. Designed for recording, arrangement and mixing, it emulates a recording studio, with a mixing desk, a rack of virtual instruments and effects and an audio and MIDI sequencer. Record can be used either as a complete virtual recording studio in itself, or together with Propellerhead Software's Reason.
This is a glossary of jazz and popular music terms that are likely to be encountered in printed popular music songbooks, fake books and vocal scores, big band scores, jazz, and rock concert reviews, and album liner notes. This glossary includes terms for musical instruments, playing or singing techniques, amplifiers, effects units, sound reinforcement equipment, and recording gear and techniques which are widely used in jazz and popular music. Most of the terms are in English, but in some cases, terms from other languages are encountered.
Amplifier modeling is the process of emulating a physical amplifier such as a guitar amplifier. Amplifier modeling often seeks to recreate the sound of one or more specific models of vacuum tube amplifiers and sometimes also solid state amplifiers.