Exciter (effect)
Encyclopedia
An Exciter is an audio signal processing
technique used to enhance a signal by dynamic equalization
, phase manipulation, harmonic synthesis of (usually) high frequency signals, and through the addition of subtle harmonic distortion. Dynamic Equalization involves variation of the Equalizer characteristics in the time domain as a function of the input. Due to the varying nature, noise
is reduced compared to static equalizers. Harmonic
synthesis involves the creation of higher order harmonics from the fundamental frequency
signals present in the recording. As noise usually decreases with the frequency band, the harmonics are derived from a purer frequency band resulting in clearer highs. Exciters are also used to synthesize harmonics of low frequency signals to simulate deep bass in smaller speakers.
Originally made in valve (tube
) based equipment, they are now implemented as part of a digital signal processor
, often trying to emulate analogue Exciters. Exciters are mostly found as plug-ins for sound editing software and in sound enhancement processors.
and musically related synthesized harmonics to audio signals. The first Aural Exciter units were available in the mid-1970s, exclusively on the rental basis of $30 per minute of finished recorded time. The unit became so popular, especially with the Los Angeles
music
and recording studio
scene, that Aphex had to move to Hollywood. In the 1970s, certain recording artists, including Jackson Browne
, Linda Ronstadt
and James Taylor
stated in their liner notes
"This album was recorded using the Aphex Aural Exciter." Other users included Donna Summer
, Paul McCartney
, Fleetwood Mac
, Olivia Newton-John
, Alan Parsons
and Warren Zevon
.
Recognizing that there was a much bigger market than just the rental business, Aphex started selling the professional units, and introduced two low-cost models: Type B and Type C. The Aural Exciter circuit is now licensed by a growing list of manufacturers, including Yamaha
, MacKenzie, Gentner, Emu and Bogen. The original Aphex Aural Exciter, first offered in 1975, came without the Big Bottom circuit, which was added in 1992. Later revisions of theAphex Aural Exciter included the Model 104 Type C and Type C2 units. Aphex released in 2001 the Model 204 Aural Exciter and Optical Big Bottom, yet another refinement of the original unit. According to Aphex, the Model 204 updates the Aural Exciter and Big Bottom processor blocks with improved circuitry, including an optical gain-control element for the Big Bottom compressor.
. Most are analogue signal processors, although a few digital units began to appear in the 2000s. The BBE Sonic Maximiser utilises a similar process of frequency-dependent phase shifting, as do other brands to a varying extent.
Audio signal processing
Audio signal processing, sometimes referred to as audio processing, is the intentional alteration of auditory signals, or sound. As audio signals may be electronically represented in either digital or analog format, signal processing may occur in either domain...
technique used to enhance a signal by dynamic equalization
Equalization
Equalization, is the process of adjusting the balance between frequency components within an electronic signal. The most well known use of equalization is in sound recording and reproduction but there are many other applications in electronics and telecommunications. The circuit or equipment used...
, phase manipulation, harmonic synthesis of (usually) high frequency signals, and through the addition of subtle harmonic distortion. Dynamic Equalization involves variation of the Equalizer characteristics in the time domain as a function of the input. Due to the varying nature, noise
Noise
In common use, the word noise means any unwanted sound. In both analog and digital electronics, noise is random unwanted perturbation to a wanted signal; it is called noise as a generalisation of the acoustic noise heard when listening to a weak radio transmission with significant electrical noise...
is reduced compared to static equalizers. Harmonic
Harmonic
A harmonic of a wave is a component frequency of the signal that is an integer multiple of the fundamental frequency, i.e. if the fundamental frequency is f, the harmonics have frequencies 2f, 3f, 4f, . . . etc. The harmonics have the property that they are all periodic at the fundamental...
synthesis involves the creation of higher order harmonics from the fundamental frequency
Fundamental frequency
The fundamental frequency, often referred to simply as the fundamental and abbreviated f0, is defined as the lowest frequency of a periodic waveform. In terms of a superposition of sinusoids The fundamental frequency, often referred to simply as the fundamental and abbreviated f0, is defined as the...
signals present in the recording. As noise usually decreases with the frequency band, the harmonics are derived from a purer frequency band resulting in clearer highs. Exciters are also used to synthesize harmonics of low frequency signals to simulate deep bass in smaller speakers.
Originally made in valve (tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
) based equipment, they are now implemented as part of a digital signal processor
Digital signal processor
A digital signal processor is a specialized microprocessor with an architecture optimized for the fast operational needs of digital signal processing.-Typical characteristics:...
, often trying to emulate analogue Exciters. Exciters are mostly found as plug-ins for sound editing software and in sound enhancement processors.
Aural Exciter
The Aural Exciter was one of the first exciter effects. The Aural Exciter effect was developed in the mid-1970s by Aphex Electronics. The Aural Exciter enhances clarity and intelligibility by adding phase shiftPhase (waves)
Phase in waves is the fraction of a wave cycle which has elapsed relative to an arbitrary point.-Formula:The phase of an oscillation or wave refers to a sinusoidal function such as the following:...
and musically related synthesized harmonics to audio signals. The first Aural Exciter units were available in the mid-1970s, exclusively on the rental basis of $30 per minute of finished recorded time. The unit became so popular, especially with the Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...
music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
and recording studio
Recording studio
A recording studio is a facility for sound recording and mixing. Ideally both the recording and monitoring spaces are specially designed by an acoustician to achieve optimum acoustic properties...
scene, that Aphex had to move to Hollywood. In the 1970s, certain recording artists, including Jackson Browne
Jackson Browne
Jackson Browne is an American singer-songwriter and musician who has sold over 17 million albums in the United States alone....
, Linda Ronstadt
Linda Ronstadt
Linda Ronstadt is an American popular music recording artist. She has earned eleven Grammy Awards, two Academy of Country Music awards, an Emmy Award, an ALMA Award, numerous United States and internationally certified gold, platinum and multiplatinum albums, in addition to Tony Award and Golden...
and James Taylor
James Taylor
James Vernon Taylor is an American singer-songwriter and guitarist. A five-time Grammy Award winner, Taylor was inducted into the Rock & Roll Hall of Fame in 2000....
stated in their liner notes
Liner notes
Liner notes are the writings found in booklets which come inserted into the compact disc jewel case or the equivalent packaging for vinyl records and cassettes.-Origin:...
"This album was recorded using the Aphex Aural Exciter." Other users included Donna Summer
Donna Summer
LaDonna Adrian Gaines , known by her stage name, Donna Summer, is an American singer/songwriter who gained prominence during the disco era of the 1970s. She has a mezzo-soprano vocal range. Summer is a five-time Grammy winner and was the first artist to have three consecutive double albums reach...
, Paul McCartney
Paul McCartney
Sir James Paul McCartney, MBE, Hon RAM, FRCM is an English musician, singer-songwriter and composer. Formerly of The Beatles and Wings , McCartney is listed in Guinness World Records as the "most successful musician and composer in popular music history", with 60 gold discs and sales of 100...
, Fleetwood Mac
Fleetwood Mac
Fleetwood Mac are a British–American rock band formed in 1967 in London.The only original member present in the band is its eponymous drummer, Mick Fleetwood...
, Olivia Newton-John
Olivia Newton-John
Olivia Newton-John AO, OBE is a singer and actress. She is a four-time Grammy award winner who has amassed five No. 1 and ten other Top Ten Billboard Hot 100 singles and two No. 1 Billboard 200 solo albums. Eleven of her singles and 14 of her albums have been certified gold by the RIAA...
, Alan Parsons
Alan Parsons
Alan Parsons is a British audio engineer, musician, and record producer. He was involved with the production of several significant albums, including The Beatles' Abbey Road and Let It Be, as well as Pink Floyd's The Dark Side of the Moon for which Pink Floyd credit him as an important contributor...
and Warren Zevon
Warren Zevon
Warren William Zevon was an American rock singer-songwriter and musician noted for including his sometimes sardonic opinions of life in his musical lyrics, composing songs that were sometimes humorous and often had political or historical themes.Zevon's work has often been praised by well-known...
.
Recognizing that there was a much bigger market than just the rental business, Aphex started selling the professional units, and introduced two low-cost models: Type B and Type C. The Aural Exciter circuit is now licensed by a growing list of manufacturers, including Yamaha
Yamaha (manufacturer)
is a multinational corporation and conglomerate based in Japan with a wide range of products and services, predominantly musical instruments, electronics, motorcycles and power sports equipment.-History:...
, MacKenzie, Gentner, Emu and Bogen. The original Aphex Aural Exciter, first offered in 1975, came without the Big Bottom circuit, which was added in 1992. Later revisions of theAphex Aural Exciter included the Model 104 Type C and Type C2 units. Aphex released in 2001 the Model 204 Aural Exciter and Optical Big Bottom, yet another refinement of the original unit. According to Aphex, the Model 204 updates the Aural Exciter and Big Bottom processor blocks with improved circuitry, including an optical gain-control element for the Big Bottom compressor.
Other brands
Functionally similar units from competing manufacturers are generically known either as "psychoacoustic processors", "psychoacoustic exciters", "harmonic exciters", or "enhancers". In the 1990s and 2000s, broadly comparable products now available from BBE, Joemeek, SPL and BehringerBehringer
Behringer is an audio equipment company founded by Uli Behringer in 1989, in Willich, Germany. Behringer was listed as the 14th largest manufacturer of music products in 2007. Behringer is a multi-national group of companies, with direct marketing presence in 10 countries or territories and a...
. Most are analogue signal processors, although a few digital units began to appear in the 2000s. The BBE Sonic Maximiser utilises a similar process of frequency-dependent phase shifting, as do other brands to a varying extent.
Uses
- Unlike traditional equalizer devices, exciters are less likely to add noise and hiss, which make them useful in enhancing dull recordings, especially analog reel-to-reel tape recordings that have lost their "sparkle" due to repeated overdubs.
- Exciters are also used for restoring old recordings by adding lost spectral content
- Exciters are increasingly implemented as an audio enhancement for hardware and software media players
- Exciters can be useful for vinyl DJs to add a different sound quality to parts of their DJ set or "brighten up" a very old record that has begun to sound dull.
- Exciters are also sold in a "stompbox" pedal format, in units designed for use with an electric guitarElectric guitarAn electric guitar is a guitar that uses the principle of direct electromagnetic induction to convert vibrations of its metal strings into electric audio signals. The signal generated by an electric guitar is too weak to drive a loudspeaker, so it is amplified before sending it to a loudspeaker...
, electric bassElectric BassElectric bass can mean:*Electric upright bass, the electric version of a double bass*Electric bass guitar*Bass synthesizer*Big Mouth Billy Bass, a battery-powered singing fish...
, or electronic keyboards.
External links
- The Aphex Vintage Aural Exciter Plugin by Waves
- Enhancers article on Sound on SoundSound on SoundSound on Sound is an independently-owned monthly music technology magazine published by SOS Publications Group, based in Cambridge, UK. The magazine includes product tests of electronic musical performance and recording devices, and interviews with industry professionals...
- Enhancers FAQ on Sound on SoundSound on SoundSound on Sound is an independently-owned monthly music technology magazine published by SOS Publications Group, based in Cambridge, UK. The magazine includes product tests of electronic musical performance and recording devices, and interviews with industry professionals...