Fulltone Fat-Boost - User Manual

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Summary

Product Features

Drive Control

Adjusts FET bias for tone shaping, adding fatness, and even order harmonics.

Tone Control

Passive high-end roll-off to 'brown up' the sound. Full CW bypasses the circuit.

Volume Control

Determines the amount of signal that exits the pedal.

Sample Settings

Provides example settings for Clean Boost and Tube amp Overdrive tones.

Warranty Information

Details the 5-year warranty, coverage, and return process.

DC Power Options

Explains power requirements, voltage effects, and adapter specifications.

Overview

The Fulltone Fat-Boost™ is a Class-A, FET (Field-Effect-Transistor) driven circuit designed to enhance your guitar tone with a range of boosting and tonal shaping capabilities. It offers up to 30dB of clean boost, allowing you to increase your signal volume without altering your fundamental sound. Beyond simple volume enhancement, the pedal provides options to "fatten" or subtly distort your tone, brighten the sound, and introduce even-order harmonics, which are often associated with the pleasing characteristics of tube amplifiers.

A key feature of the Fat-Boost is its True-Bypass switching, ensuring that when the pedal is disengaged, your guitar signal passes through unaffected, preserving your original tone. The pedal also incorporates a special 180-degree lens cover, designed for easy viewing of the controls from various angles, which can be particularly useful in live performance settings or on a crowded pedalboard.

The design leverages the behavior of FETs, which, when properly implemented in a circuit, mimic the characteristics of vacuum tubes. This means that the pedal's "clipping" or distortion is smooth and musical, avoiding the harsh, "buzzy" or "spiky" sounds often associated with less refined solid-state distortion circuits. Additionally, the FETs contribute a subtle compression to the signal. This compression helps to even out the volume dynamics of your playing, making your recordings and live performances sound more consistent and polished. Notes tend to sustain longer without becoming distorted, providing a more dynamic and expressive playing experience, especially at lower "living room" volumes where you want the feel of a cranked amp without the excessive loudness.

The Fat-Boost is highly versatile in its application. It excels when placed in front of vintage amplifiers, effectively "goosing" them to achieve earlier breakup and richer overdrive tones. Similarly, it can be used with master-volume amplifiers to push them harder than would be possible with just the guitar's output alone, resulting in more saturated and powerful sounds. Beyond electric guitar, the pedal is also highly effective with bass guitars, adding girth and presence to the low end. Acoustic guitar pickups can also benefit from the Fat-Boost, gaining increased clarity and fullness.

One of its most significant benefits is its ability to combat tone loss over long cable runs. When placed at the end of a pedalboard effects chain, the Fat-Boost can completely eliminate the signal degradation caused by extended lengths of guitar cable, allowing you to confidently use 30 feet or more of cable without sacrificing your tone. This ensures that your signal remains strong and clear, regardless of your stage setup or studio configuration.

The pedal features three primary control knobs: Drive, Tone, and Volume. The Drive knob is an 11-position detented potentiometer that adjusts the bias of the FETs. It functions much like a Preamp Volume knob on a Master-Volume tube amplifier. Turning the knob counter-clockwise (CCW) results in very neutral, honest tones with minimal thickening of the original notes. As you turn the knob clockwise (CW), the FETs gently clip, mimicking the sound of a cranked tube amp. This action adds fatness, introduces even-order harmonics, and can also add a little more treble (hi-end frequencies). Higher Drive knob settings will generally yield more overall volume. It's normal to hear a slight scraping noise when adjusting this knob, which is simply the sound of the FETs rebiasing and not an indication of a noise problem.

The Tone knob is a passive high-end (Treble) roll-off control. Turning it full CW takes the tone control completely out of the circuit, providing the brightest possible sound. As you turn it CCW, it attenuates the treble frequencies, allowing you to "brown up" your sound. The neutral setting of the tone control can vary depending on factors such as the Drive knob setting and the amplifier's volume and settings. A common setting that often works well is 12 O'clock.

The Volume knob directly controls the amount of signal that exits the pedal, allowing you to set the overall output level to match your desired volume or to drive subsequent pedals or your amplifier harder.

For example, a "Clean Boost" setting could involve the Drive knob at 11 O'clock, Volume between 1 and 5 O'clock, and Tone at 12 O'clock. To achieve a "Tube amp Overdrive" sound, you might set the Drive to Full CW, Volume between 10 and 12 O'clock, and Tone at 'O'clock. These are just sample settings, and the pedal encourages experimentation to find your preferred sounds.

Regarding power, the Fat-Boost can be operated using the supplied 9-volt battery or with an external DC adapter. It is compatible with any voltage between 9 and 18 Volts DC, provided the adapter has a standard 2.1mm size with a Center-Pin/Negative configuration. Using higher voltages (e.g., 18V) can significantly impact the pedal's sonic characteristics, resulting in a cleaner, louder, and more dynamic sound. However, it is crucial to use a standard 9-volt DC/Negative Center Pin configured adapter (such as the Fulltone FPS-1) to avoid voiding the warranty. Any damage resulting from the use of an incompatible adapter will not be covered.

Maintenance of the Fat-Boost is straightforward. Fulltone products come with a 5-year warranty for the original owner, requiring proof of purchase. This warranty covers damage caused by manufacturing errors but explicitly excludes any modifications or repairs performed by anyone other than Fulltone without prior written consent. Footswitches are also warranted for 5 years, but batteries are not covered. For any warranty work, the customer is responsible for shipping costs in advance, and all warranty service must be scheduled via a phone call. A Return Authorization Form (RA Form), available via email or fax, must accompany any returned product. Fulltone Musical Products Inc. is not responsible for injuries or damages to other items related or unrelated to the use of their products. This emphasis on proper usage and authorized service ensures the longevity and optimal performance of your Fat-Boost pedal.