The Fulltone 2B JFET Booster is a compact clean boost pedal that delivers up to 20dB of JFET-driven, high-headroom boost, with a dynamic knob that controls a germanium diode limiter to soften transient spikes. Premier Guitar's reviewer called it "one of the finest I've ever used" among clean boosts1.
What it does to your sound
Premier Guitar's reviewer described the 2B's sound as "airy, detailed, and smooth," a wide-spectrum harmonic boost that is not too trebly1. That puts it in a different family from a treble booster like the Fulltone Ranger, which lifts only the top end. As a clean boost, it is built to push an amp harder or lift a part in a mix without changing the core tone, and the high-headroom design means it stays clean where lesser circuits would clip1.
The dynamic knob and germanium limiter
The 2B's most distinctive control is its dynamic knob. Premier Guitar explains: "This little knob controls a germanium diode limiter that softens transient spikes." Turned clockwise, it gives a progressively more controlled and contained boost signal1.
In practice, that means the pedal can tame the sharpest pick attacks while keeping the boost intact. Players with bright guitars or aggressive picking styles can dial in as much or as little of that softening as they want, which is unusual on a pedal this simple1.
Where it came from
Premier Guitar describes the 2B as "essentially the clean boost section of the excellent Fulltone Full-Drive 3"1, packaged on its own pedal with the dynamic control added. Players who like the boost side of the Fulltone Fulldrive 3 but do not need its overdrive channels get that circuit standalone. Fulltone also builds other boost-adjacent pedals, such as the Fulltone Catalyst, and the 2B sits in the company's range alongside its overdrive pedals like the Full-Drive 2 V2. For more on the type, see the site's guide to Boost Pedals.
What reviewers said
Premier Guitar's quick-hit review tested the 2B with a Rickenbacker 330, a Fender Jaguar with Seymour Duncan "Jaguar Hot" pickups, a silverface Fender Bassman with Warehouse G12C/S speakers, a Vox Pathfinder, and a '72 Fender Champ1. The reviewer's verdict:
"in fact it's one of the finest I've ever used"
Premier Guitar's reviewer found the 2B to be one of the finest clean boosts the reviewer has ever used overall1.
The reviewer also praised the "compact, sturdy, and elegant" enclosure1.
Videos
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Questions
Is the Fulltone 2B JFET Booster a buffered pedal?
Yes. Premier Guitar's review notes that the 2B works as a buffer whether the pedal is on or off, so it can condition your signal even when the boost is bypassed. That makes it useful at the end of a long pedalboard chain, not just as a boost.
Can the Fulltone 2B run at 18V?
Yes. Premier Guitar reports that the 2B can be operated at 18V for extra headroom, which gives the boost circuit more room before it clips. Players who want the cleanest possible boost at high levels may find that useful.
How much boost does the Fulltone 2B give?
Premier Guitar describes the 2B as delivering up to 20dB of JFET-driven, refined, high-headroom muscle. That is enough to push an amp into breakup or lift a solo above a band mix.
Does the 2B JFET Booster add a lot of treble?
Premier Guitar's reviewer described the sound as airy, detailed, and smooth, and noted it is not too trebly. It is a wide-spectrum harmonic boost rather than a treble booster.
What is the 2B based on?
Premier Guitar describes the 2B as essentially the clean boost section of the Fulltone Full-Drive 3, packaged on its own with the addition of the dynamic control.
Sources (1)
- Quick Hit: Fulltone 2B JFET Booster Review, Premier Guitar, 2015-12-22
