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Rat Dist and Fat Rat: based on Pro Co Rat
The “RAT” is a famous distortion pedal by Pro Co. The black box is easily recognizable. Famous users include David Gilmour and Jeff Beck. It’s believed to be responsible for the distorted chords which kick in so hard in Radiohead’s Creep.
Pro Co made many, many versions of the Rat, including the "RAT 2", "Turbo RAT", "Fat Rat", "You Dirty Rat", "Deucetone" etc.
There’s a dedicated site for the RAT products, including sound samples and history.
More background, courtesy of Tone Report. And a Guitar Interactive article.
The pedal has three knobs:
The passive Filter knob is crucial to its tone. In the very first versions it was a conventional tone control, which was then changed to a treble cutting filter. Make sure to experiment with it in the model, but be aware: it works the opposite way of the real pedal.
The FAT RAT model is a modified version of the RAT, according to the Axe-Fx II’s Owners’s Manual. Which modified version that is has not been disclosed. Quite possible it’s Pro Co’s own FAT RAT, with its germanium diode, because the model's Clip Type is "germanium", as opposed to the “Rat Dist” model's "silicon" Clip Type. The Fat Rat model provides loads more gain than the Rat Dist model.
According to the firmware release notes, Fractal's Audio Rat Dist model was last updated in Quantum 5.x. The Fat Rat isn’t mentioned.
Of course the Drive block allows us to adjust far more things than the modeled pedal: Bias, Slew, Mix, Low Cut, High Cut and other parameters are available to us. But that's beyond the scope of this thread. Those parameters are discussed in the manual and wiki.
For some reason, the Rat Dist model is often seen in conjunction with the SYNTH block.
Placed before SYNTH it will warm up and smoothen the sound.
About CPU usage:
Link to the list of published threads
Rat Dist and Fat Rat: based on Pro Co Rat
The “RAT” is a famous distortion pedal by Pro Co. The black box is easily recognizable. Famous users include David Gilmour and Jeff Beck. It’s believed to be responsible for the distorted chords which kick in so hard in Radiohead’s Creep.
Pro Co made many, many versions of the Rat, including the "RAT 2", "Turbo RAT", "Fat Rat", "You Dirty Rat", "Deucetone" etc.
Wikipedia:
“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. 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 fame gained by its use by several artists.
“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. 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 fame gained by its use by several artists.
The Pro Co "The RAT" is a distortion pedal with a quite simple circuit, which can be broken down into four simpler blocks: distortion stage, tone control, output stage and power supply. The design is based around a single opamp, originally the Motorola LM308 (switched to Texas Instruments OP07DP around 2002-2003). 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 construction method is similar to the Boss DS-1 distortion pedal, although there are major differences between the two circuits. A major difference is the opamp used (the LM308), known for its poor slew rate; it largely accounts for the sonic difference between the two pedals.”
There’s a dedicated site for the RAT products, including sound samples and history.
More background, courtesy of Tone Report. And a Guitar Interactive article.
The pedal has three knobs:
- Distortion: controls the amount of distortion (model: Drive).
- Filter: operates as treble cut (model: Tone).
- Volume: controls the output level (model: Level).
The passive Filter knob is crucial to its tone. In the very first versions it was a conventional tone control, which was then changed to a treble cutting filter. Make sure to experiment with it in the model, but be aware: it works the opposite way of the real pedal.
Fractal Audio:
"The filter knob has been modeled but it works backwards.”
"The filter knob has been modeled but it works backwards.”
The FAT RAT model is a modified version of the RAT, according to the Axe-Fx II’s Owners’s Manual. Which modified version that is has not been disclosed. Quite possible it’s Pro Co’s own FAT RAT, with its germanium diode, because the model's Clip Type is "germanium", as opposed to the “Rat Dist” model's "silicon" Clip Type. The Fat Rat model provides loads more gain than the Rat Dist model.
According to the firmware release notes, Fractal's Audio Rat Dist model was last updated in Quantum 5.x. The Fat Rat isn’t mentioned.
Of course the Drive block allows us to adjust far more things than the modeled pedal: Bias, Slew, Mix, Low Cut, High Cut and other parameters are available to us. But that's beyond the scope of this thread. Those parameters are discussed in the manual and wiki.
Personal note:
I owned an 80’s Rat (the "v2", not the current RAT 2), with the Pro Co logo on top. I had it modded by Robert Keeley, adding a 3-way switch among others. It was part of the pile of gear I sold when migrating to the Axe-Fx Ultra. I primarily use the model in combination with Vox-type amps because they just match very well IMHO. I pretty much set the controls the same way as on the real pedal: low Drive, high Level, and bit of treble cut. Too much gain and it becomes fuzzy.
I don’t care much for the Fat Rat model.
I owned an 80’s Rat (the "v2", not the current RAT 2), with the Pro Co logo on top. I had it modded by Robert Keeley, adding a 3-way switch among others. It was part of the pile of gear I sold when migrating to the Axe-Fx Ultra. I primarily use the model in combination with Vox-type amps because they just match very well IMHO. I pretty much set the controls the same way as on the real pedal: low Drive, high Level, and bit of treble cut. Too much gain and it becomes fuzzy.
I don’t care much for the Fat Rat model.
For some reason, the Rat Dist model is often seen in conjunction with the SYNTH block.
Placed before SYNTH it will warm up and smoothen the sound.
About CPU usage:
- Fractal Audio's Drive models take up varying amounts of CPU. The Rat Dist and Fat Rat models require a moderate amount.
- When a Drive block is engaged, CPU percentage will rise during playing, because CPU usage is "amplitude dependent".
Link to the list of published threads
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