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FET Preamp: based on BOSS FA-1 Fet Amplifier
The FET Preamp Drive model is probably based on the rare BOSS FA-1 Fet Amplifier, from their short-lived Pocket Series. It’s a pocket-size amp (not a pedal), designed to attach to a player’s belt, without an On/Off switch.
Around the release of firmware 17 it became known that guitar player The Edge (U2) was using the Axe-Fx II. The Edge is known for his use of Korg’s SDD 3000 and the FA-1. The SDD Preamp and FET Preamp models currently aren't mentioned in the current Axe-Fx II Owner’s Manual, but I'd say it's pretty safe to assume that these are based on the venerable devices mentioned above, and that there’s a correlation between The Edge’s endorsement of Fractal Audio gear and the addition of these models.
It’s hard to find an original FA-1 nowadays. If you do find one, it will be expensive, mainly because of its adoption by The Edge. It has been cloned a lot though.
FET is abbreviation of Field-Effect-Transistor, a semi-conductor. FETs are used in pedals as well as amplifiers. In products for guitars you’ll encounter the MOSFET and JFET types the most.
FET is implemented as a Clip Type in Fractal Audio’s Drive models. The FET Boost and FET Preamp models are showcases.
Although it was designed to operate as a portable amp, the FA-1 primarily is used as a boost. Slamming the input of amps to kick them into overdrive often results in better tone than using an overdrive pedal because the increased amp distortion is natural and transparent and the tone gets fatter. It enhances the characteristics of the amp instead of changing it. Boosts are often used before vintage amps like Vox and Plexis. The FET Preamp model can be used in the same way. Alternative boosting solutions are discussed in the FAS Boost thread.
The FA-1 has these controls:
Link to the list of published threads
FET Preamp: based on BOSS FA-1 Fet Amplifier
The FET Preamp Drive model is probably based on the rare BOSS FA-1 Fet Amplifier, from their short-lived Pocket Series. It’s a pocket-size amp (not a pedal), designed to attach to a player’s belt, without an On/Off switch.
Around the release of firmware 17 it became known that guitar player The Edge (U2) was using the Axe-Fx II. The Edge is known for his use of Korg’s SDD 3000 and the FA-1. The SDD Preamp and FET Preamp models currently aren't mentioned in the current Axe-Fx II Owner’s Manual, but I'd say it's pretty safe to assume that these are based on the venerable devices mentioned above, and that there’s a correlation between The Edge’s endorsement of Fractal Audio gear and the addition of these models.
It’s hard to find an original FA-1 nowadays. If you do find one, it will be expensive, mainly because of its adoption by The Edge. It has been cloned a lot though.
FET is abbreviation of Field-Effect-Transistor, a semi-conductor. FETs are used in pedals as well as amplifiers. In products for guitars you’ll encounter the MOSFET and JFET types the most.
Wikipedia:
“The field-effect transistor (FET) is a transistor that uses an electric field to control the shape and hence the electrical conductivity of a channel of one type of charge carrier in a semiconductor material. FETs are also known as unipolar transistors since they involve single-carrier-type operation. The FET has several forms, but all have high input impedance. While the conductivity of a non-FET is regulated by the input current (the emitter to base current) and so has a low input impedance, a FET's conductivity is regulated by a voltage applied to a terminal (the gate) which is insulated from the device. The applied gate voltage imposes an electric field into the device, which in turn attracts or repels charge carriers to or from the region between a source terminal and a drain terminal. The density of charge carriers in turn influences the conductivity between the source and drain. (...) The most commonly used FET is the MOSFET.”
Fulltone:
“FET’s can behave like Tubes in a properly designed circuit. They can “clip” (distort) in a pleasing way instead of being buzzy or spiky sounding (like a Transistor) and can also add a subtle Limiting to the signal which can even-out the volume making your Live and Recorded tones more pleasing to the ear.”
“The field-effect transistor (FET) is a transistor that uses an electric field to control the shape and hence the electrical conductivity of a channel of one type of charge carrier in a semiconductor material. FETs are also known as unipolar transistors since they involve single-carrier-type operation. The FET has several forms, but all have high input impedance. While the conductivity of a non-FET is regulated by the input current (the emitter to base current) and so has a low input impedance, a FET's conductivity is regulated by a voltage applied to a terminal (the gate) which is insulated from the device. The applied gate voltage imposes an electric field into the device, which in turn attracts or repels charge carriers to or from the region between a source terminal and a drain terminal. The density of charge carriers in turn influences the conductivity between the source and drain. (...) The most commonly used FET is the MOSFET.”
Fulltone:
“FET’s can behave like Tubes in a properly designed circuit. They can “clip” (distort) in a pleasing way instead of being buzzy or spiky sounding (like a Transistor) and can also add a subtle Limiting to the signal which can even-out the volume making your Live and Recorded tones more pleasing to the ear.”
FET is implemented as a Clip Type in Fractal Audio’s Drive models. The FET Boost and FET Preamp models are showcases.
Although it was designed to operate as a portable amp, the FA-1 primarily is used as a boost. Slamming the input of amps to kick them into overdrive often results in better tone than using an overdrive pedal because the increased amp distortion is natural and transparent and the tone gets fatter. It enhances the characteristics of the amp instead of changing it. Boosts are often used before vintage amps like Vox and Plexis. The FET Preamp model can be used in the same way. Alternative boosting solutions are discussed in the FAS Boost thread.
The FA-1 has these controls:
- Volume: controls the output volume (model: probably Level).
- Bass and Treble: active tone controls. While the model also provides active Bass and Treble controls, they visually don't exactly behave the same as on the pedal.
- Flat / Low Cut switch: a 6dB low cut at 200 Hz, designed to prevent feedback (“howling”) when using the FA-1 with acoustic instruments. Similar behavior can be achieved in the Model using the Low Cut control.
Personal notes:
About CPU:- Can't deny it: a little bit of FET boosting in front of the amp does add recognizable Edge-ness to the tone.
- The FA-1's design goal (amplifier) raises the question if its model can be used in our Fractal Devices as a substitute for a dedicated amp block. This would allow FX8 owners to make use of a basic virtual amp, allow AX8 users to add a 2nd "amp" path and users of the Axe-Fx to add a 3rd amp-like block. Try it for yourself and share your experiences below.
- Fractal Audio's Drive models take up varying amounts of CPU. The FET Preamp model requires 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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