Pro Co Rat
Encyclopedia
The Pro Co "The RAT" is a guitar effects pedal produced by Pro Co Sound. The original RAT was developed in the basement of Pro Co's Kalamazoo, Michigan facility in 1978. Numerous variations of the original RAT pedal are still being produced today.

The basic RAT has changed in appearance over the years, but its tone has remained largely the same, although there is a general consensus that the mid 1980s versions are superior sonically. Pro Co has also introduced tonal variations of the RAT, including the Turbo RAT, and You Dirty RAT, among others.

The Pro Co RAT became very popular in the early 1980s, thanks in part to notoriety gained by its use by artists such as Jeff Beck
Jeff Beck
Geoffrey Arnold "Jeff" Beck is an English rock guitarist. He is one of three noted guitarists to have played with The Yardbirds...

 and Joe Walsh
Joe Walsh
Joseph Fidler "Joe" Walsh is an American musician, songwriter, record producer, and actor. He has been a member of three commercially successful bands, the James Gang, Barnstorm, and the Eagles, and has experienced notable success as a solo artist and prolific session musician, especially with B.B...

. Since that time, the RAT has been used by some of the most influential guitarists in the world. This list includes Tado Jimenez
Tado Jimenez
Arvin "Tado" Jimenez, commonly known as Tado, is a Filipino comedian, actor, radio personality and businessman. His nickname "Tado" comes from a Tagalog expletive he frequently blurted out...

, Francis Dunnery
Francis Dunnery
Francis Dunnery is an English musician, singer-songwriter, record producer and record label owner. He is best known as a solo performer , and for fronting the original lineup of the band It Bites between 1982 and 1990 .Dunnery served as a sideman and...

, Kurt Rosenwinkel
Kurt Rosenwinkel
Kurt Rosenwinkel is an American jazz guitarist and keyboardist who came to prominence in the 1990s.-Biography:He attended the Berklee School of Music for two and a half years before leaving in his junior year to tour with Gary Burton, the dean of the school at the time...

, Matt Bellamy, David Gilmour
David Gilmour
David Jon Gilmour, CBE, D.M. is an English rock musician and multi-instrumentalist who is best known as the guitarist, one of the lead singers and main songwriters in the progressive rock band Pink Floyd. In addition to his work with Pink Floyd, Gilmour has worked as a producer for a variety of...

, Kevin Eubanks
Kevin Eubanks
Kevin Tyrone Eubanks is an American jazz guitarist and composer who was the leader of the Tonight Show Band with host Jay Leno from 1995 to 2010. He also led The Primetime Band on the short-lived The Jay Leno Show.- Personal background :Eubanks was born into a musical family...

, Thom Yorke
Thom Yorke
Thomas "Thom" Edward Yorke is an English musician who is the lead vocalist and principal songwriter for Radiohead. He mainly plays guitar and piano, but he has also played drums and bass guitar...

, Bill Frisell
Bill Frisell
William Richard "Bill" Frisell is an American guitarist and composer.One of the leading guitarists in jazz since the late 1980s, Frisell's eclectic music touches on progressive folk, classical music, country music, noise and more...

, John Scofield
John Scofield
John Scofield , often referred to as "Sco," is an American jazz guitarist and composer, who has played and collaborated with Miles Davis, Dave Liebman, Joe Henderson, Charles Mingus, Joey Defrancesco, Herbie Hancock, Pat Metheny, Bill Frisell, Pat Martino, Mavis Staples, Phil Lesh, Billy Cobham,...

, James Dean Bradfield
James Dean Bradfield
James Dean Bradfield is the lead guitarist and vocalist for the Welsh rock band Manic Street Preachers.- Early life :...

, John Christ
John Christ
John Christ, born John Wolfgang Knoll on , is a musician best known as the original guitarist for the metal band Danzig. He has been known for his bluesy metal sound and frequent use of the pinch harmonic...

, Dave Grohl
Dave Grohl
David Eric "Dave" Grohl is an American rock musician, multi-instrumentalist, and singer-songwriter who is the lead vocalist, guitarist, and primary songwriter for Foo Fighters; the former drummer for Nirvana and Scream; and the current drummer for Them Crooked Vultures...

, Justin Chancellor
Justin Chancellor
Justin Gunnar Walter Chancellor is an English musician formerly in the band Peach but best known as the bass player for Grammy Award-winning rock band Tool. Chancellor is of Norwegian and English descent...

, Kevin Shields
Kevin Shields
Kevin Patrick Shields is an American-born, Irish vocalist, guitarist, and producer of alternative rock band My Bloody Valentine....

, Andy Summers
Andy Summers
Andy Summers is an English guitarist born in Poulton-le-Fylde, Lancashire, England. Best known as the guitarist for rock band The Police, he has also recorded twelve solo albums, collaborated with many other artists, toured extensively under his own name, published several books, and composed...

, Thurston Moore
Thurston Moore
Thurston Joseph Moore is an American musician best known as a singer, songwriter and guitarist of Sonic Youth. He has also participated in many solo and group collaborations outside of Sonic Youth, as well as running the Ecstatic Peace! record label...

, Stephen Malkmus
Stephen Malkmus
Stephen Joseph Malkmus is an indie rock musician and icon, and a member of the band Pavement. He currently performs with Stephen Malkmus and the Jicks.-Early years:...

 and Scott Kannberg
Scott Kannberg
Scott "Spiral Stairs" Kannberg is a musician best known for being a founding member of the indie-rock band Pavement.-Career:...

 of Pavement
Pavement (band)
Pavement is an American alternative rock band that formed in Stockton, California in 1989. In their career, they achieved a significant cult following, and they were called the best band of the 1990s by prominent music critics Robert Christgau and Stephen Thomas Erlewine...

, Paul Reynolds
Paul Reynolds
Paul Reynolds may refer to:*Paul Reynolds , Ex-footballer, convicted sex offender.*Paul Reynolds , British actor*Paul Reynolds , BBC's World Affairs correspondent...

 of A Flock of Seagulls
A Flock of Seagulls
A Flock of Seagulls are an English New Wave band originally formed by brothers Michael "Mike" Score and Alister "Ali" James Score , with Frank Maudsley , Michael Kuby , H.J...

, Graham Coxon
Graham Coxon
Graham Leslie Coxon is an English singer-songwriter, multi-instrumentalist and painter. He came to prominence as the lead guitarist, backing vocalist and occasional lead vocalist of rock band Blur, and is also a critically acclaimed solo artist, having recorded seven solo albums...

, Bernard Butler
Bernard Butler
Bernard Joseph Butler is an English musician and record producer. He first emerged in the early Britpop era with Suede. He has been hailed by some critics as the greatest guitarist of his generation, as well as one of Britain's most original and influential guitarists...

, Alex Turner
Alex Turner (musician)
Alexander David Turner is an English musician, best known as the lead vocalist, guitarist and main songwriter of the English rock band Arctic Monkeys...

, Jerry Cantrell
Jerry Cantrell
Jerry Fulton Cantrell Jr. is an American guitarist, singer, and songwriter best known for his work with the grunge/metal band Alice in Chains, as lead guitarist, backing and co-lead vocalist, and co-lyricist. He performs lead vocals on his solo projects, and is part of Alice in Chains' harmonizing...

, Peter Buck
Peter Buck
Peter Lawrence Buck , is an American rock guitarist who is best known for playing in and co-founding alternative rock band R.E.M....

, Nuno Bettencourt
Nuno Bettencourt
Nuno Duarte Gil Mendes Bettencourt is a Portuguese guitarist and singer-songwriter best known for his role as the lead guitarist of the Boston rock band Extreme whose hits include the acoustic ballads "More Than Words" and "Hole Hearted"...

, Kurt Cobain
Kurt Cobain
Kurt Donald Cobain was an American singer-songwriter, musician and artist, best known as the lead singer and guitarist of the grunge band Nirvana...

, Paranoid Time
Paranoid Time
Paranoid Time is the first EP by American hardcore punk band Minutemen. It is also the second ever release by the SST record label, founded by Black Flag's Greg Ginn and Chuck Dukowski.-History of the record:...

, James Hetfield
James Hetfield
James Alan Hetfield is the rhythm guitarist, co-founder, main songwriter, and lead vocalist for the American heavy metal band Metallica. Hetfield co-founded Metallica in October 1981 after answering a classified advertisement by drummer Lars Ulrich in the Los Angeles newspaper The Recycler,...

, Joe Perry
Joe Perry (musician)
Anthony Joseph "Joe" Perry is the lead guitarist, backing and occasional lead vocalist, and contributing songwriter for the rock band Aerosmith. He is influenced by many rock artists especially The Rolling Stones and The Beatles...

, Buzz Osborne
Buzz Osborne
Roger "Buzz" Osborne , also known as King Buzzo, is the guitarist/vocalist/songwriter and technically the only remaining founding member of the Melvins...

, Sunn O)))
Sunn O)))
Sunn O))) is an American doom metal band known for its synthesis of diverse genres including drone, ambient, noise, and black metal. Supported by a varying cast of collaborators, the band has two core members: Stephen O'Malley and Greg Anderson .-History:Sunn O))) is named after the Sunn...

, Justin Shekoski and Krist Novoselic
Krist Novoselic
Krist Anthony Novoselic II is a Croatian-American rock musician, best known for being the bassist and co-founder of the grunge band Nirvana. After Nirvana ended, Novoselic formed Sweet 75 and then Eyes Adrift, releasing one album with each band...

.

History

The origins of the Pro Co "The RAT" can be traced back to the mid-1970s, when Pro Co engineers Scott Burnham and Steve Kiraly repaired and hot-rodded existing distortion pedals, such as the Dallas Arbiter Fuzz Face
Fuzz Face
The Fuzz Face is an effects pedal used mainly by electric guitarists, and by some bass players. It is a stompbox designed to produce a distorted sound from an electric guitar. This "fuzz" sound is sometimes compared to the sound of a damaged speaker...

. Burnham decided he could build a superior product from the ground up, and designed "The RAT" pedal.

In 1978, "The RAT" was being built as a custom-order product. Only twelve of these pedals, commonly referred to as the “Bud Box" RAT, were produced. Each pedal was built in a standard project box, hand painted, and hand drilled. By 1979, as the pedal became more popular, Pro Co began mass producing them. This iteration was built in a custom designed, rectangular sheet-metal enclosure, with an L shaped removable top/back section giving access to the internals. The top panel was labeled with Pro Co Sound "The RAT" and the three control knobs as Distortion, Tone and Volume.

In 1983, Pro Co switched to a smaller, U-shaped enclosure. Finally, in 1988, the RAT2 was introduced, which included an on/off LED. Various RAT2 circuit board layouts and wiring configurations have surfaced in the last few years, including the noted "RAT3 version A and B" all under the RAT2 moniker. The RAT2 model is still available today, but is now made in China for Pro Co Sound by Neutrik.

Other models of RAT products include:
  • Juggernaut (1979)
  • R2DU (1984)
  • Turbo RAT (1989)
  • Vintage RAT (1991)
  • BRAT (1997)
  • Deucetone RAT (2002)
  • Juggernaut Bass RAT (2003)
  • You Dirty RAT (2004)
  • Chinese RAT2 (2008)
  • '85 Whiteface RAT Reissue (2010)

How it works

The Pro Co "The RAT" is a distortion pedal with a very simple circuit, based around a single op-amp
Operational amplifier
An operational amplifier is a DC-coupled high-gain electronic voltage amplifier with a differential input and, usually, a single-ended output...

, the LM308. The distortion is produced using a variable gain circuit with diodes shorting the output to ground to produce hard clipping of the input waveform. This distortion stage is followed by a passive tone filter and volume control. This is the same scheme as the Boss DS-1
Boss DS-1
The Boss DS-1 is a distortion pedal for guitar, manufactured by the Roland Corporation under the brand name Boss since 1978. The first distortion unit made by Boss, it has become a classic effect, used by many notable guitar players. Boss produced a successor, the DS-2.-Circuit design:The DS-1 has...

 distortion pedal, although there are major differences between the two circuits, therefore the sound of the two pedals are different. The most popular RAT pedal, the RAT2, features true-bypass switching.

Current product line

  • Turbo RAT
  • Deucetone RAT
  • You Dirty RAT
  • Chinese RAT2
  • '85 Whiteface RAT Reissue

Discontinued products

  • "Bud Box" RAT
  • The RAT
  • Juggernaut
  • "Small Box" RAT
  • Vintage RAT
  • BRAT
  • Roadkill (same circuit as the BRAT with a different enclosure)
  • Juggernaut Bass RAT

Popular modifications to the RAT

The RAT is a popular pedal for modifying. Some of the possible modifications include:
  • Resistor Mods: The Ruetz RAT mod which involves simply cutting the 47 Ω
    Ohm
    The ohm is the SI unit of electrical resistance, named after German physicist Georg Simon Ohm.- Definition :The ohm is defined as a resistance between two points of a conductor when a constant potential difference of 1 volt, applied to these points, produces in the conductor a current of 1 ampere,...

     resistor
    Resistor
    A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...

     to disengage half of the drive circuit. Gain is reduced somewhat and the bass is no longer attenuated. Additionally, the 560 Ω resistor controlling the lower half of the distortion filter can receive similar treatment. Either can translate to thicker (fuzzier) bass response at the expense of less distortion.
  • Toggle Switches: The Mightier Mouse mod involves a 3-way switch to select between RAT 2 (clipping via op-amp only), Turbo RAT (clipping via LEDs
    Light-emitting diode
    A light-emitting diode is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting...

    ), and MOSFET
    MOSFET
    The metal–oxide–semiconductor field-effect transistor is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925...

     clipping modes. It also shows an alternative to the Ruetz RAT mod using a potentiometer
    Potentiometer
    A potentiometer , informally, a pot, is a three-terminal resistor with a sliding contact that forms an adjustable voltage divider. If only two terminals are used , it acts as a variable resistor or rheostat. Potentiometers are commonly used to control electrical devices such as volume controls on...

     or trimpot to replace the resistor instead of simply cutting it.
  • Diode Removal: Removing one of the two silicon clipping diodes for a volume boost crunch tone.
  • Chip Substitutions: The original RAT pedals featured the LM308 op-amp which is now quite expensive. Recent RAT pedals now feature the Texas Instruments OP07DP. Other op-amps that people try include the NE5535A, NE5534AP LM741 and TL071 FET-OP. Many install an IC socket to enable easy swapping of ICs, very much similar to what people do with the Ibanez Tube Screamer
    Ibanez Tube Screamer
    The Ibanez Tube Screamer is a guitar overdrive pedal, made by Ibanez. The pedal has a characteristic mid-boosted tone popular with blues players...

    .
  • Capacitor Mods: "softening" ceramic caps replaced with silver mica or metal film caps for better tonal fidelity. These include the 30 pF cap riding the IC chip and the single 100 pF cap.
  • Power Adapter: 2.1 mm (Boss-style) 9 V DC adapter socket mod. Because the tip on the Boss-style adapter is negative, one needs to install a plastic 2.1 mm socket to avoid shorting out the barrel of the plug against the RAT's steel chassis.
  • Robert Keeley
    Robert Keeley (instrument maker)
    Robert Keeley is a British creator of effects pedals. He modifies pre-existing pedals made by companies such as Boss Corporation and as well as creating his own stomp boxes.-Pedals:...

    does a popular mod involving replacement of the existing op-amp for an original LM308, a capacitor upgrade (using film and tantalum capacitors) to improve bass response and a 3 way mode switch. The first mode is the Classic RAT which is the original RAT circuit. The second mode is the Phat RAT which has an extra diode added to the original circuit in attempt to achieve a more tube-like sound. The final mode is the Mighty Mouse in which a diode is removed from the original circuit causing it to behave more like a boost pedal.
  • Electronics modders Vodka Mods perform a popular RATsputin mod that includes dual toggle switchs to the drive and clipping sections, a Texas Instruments NE5534AP op-amp upgrade and an extra case mounted potentiometer, which allows maximum control over tonal variables.
  • Jack Orman, creator of the Fat Gnat mods, includes many details and an available e-book at his website.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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