In the world of boutique guitar gear, history is usually written by meticulous design. But every now and then, it’s written by a beautiful, catastrophic mistake.
JHS Pedals has officially announced the release of The Fumble, a standalone JFET clean boost pedal with a price tag of just $89 USD. While the pedal itself is bound to turn heads, it’s the bizarre, multi-generational history behind the circuit that is sending shockwaves through the gear community.
According to JHS founder Josh Scott, the pedal only exists because of “the biggest mistake in JHS history”—a mix-up involving John Mayer’s personal gear archive, a discontinued DIY kit, and a 1970s acoustic guitar preamp hiding inside a $400,000 Dumble amplifier.
The $400,000 Mix-Up: From NOTADÜMBLË to Fumble
The story begins in May 2025, when JHS released the NOTADÜMBLË V1, a highly anticipated solderless DIY kit meant to replicate two distinct Dumble-inspired circuits. The clean side was advertised as a reverse-engineered replica of “A Box Later”—an obscure, buffered effects loop unit built by Howard Dumble in the 1980s, which John Mayer had personally loaned to JHS.
However, a week after the massive 15,000-unit batch launched and sold out, Scott made a horrifying discovery while prepping a YouTube video: he had put the wrong circuit in the pedal.
Instead of the “A Box Later” buffer, Scott had accidentally loaded a completely different Dumble preamp circuit he had reverse-engineered for Mayer back in 2019 and forgotten about. JHS immediately owned the mistake, offered refunds, and discontinued the NOTADÜMBLË V1.
But then, something unexpected happened. Customers started raving about the “wrong” circuit.
The Secret Origin of the Dumble “FET” Tone
When JHS dug into the history of the accidental circuit—the legendary Dumble BBC-1 preamp—they uncovered a truth stranger than fiction.
The BBC-1 wasn’t actually an original Dumble design. Howard Dumble had lifted a JFET preamp circuit almost part-for-part from a budget 1970s Barcus Berry acoustic preamp meant to bridge piezo pickups into electric guitar amps.
Dumble housed it in his own enclosures for LA session players and integrated the exact same JFET stage into his iconic amplifiers, labeling it the “FET” mode.
This means the legendary Dumble FET sound found in amplifiers valued between $200,000 and $400,000 is actually a cloned 1970s acoustic guitar utility box. As JHS puts it, The Fumble is “a clone of that clone of that clone.”
Stripped-Down Tone Sweetener
Now freed from the DIY kit format, The Fumble comes fully assembled in a compact enclosure featuring a vintage football helmet graphic—a name and logo JHS had sitting in a drawer since 2012.
The Fumble is a true bypass JFET clean boost featuring an incredibly unique two-knob control layout:
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OUTPUT: A standard master volume control.
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INPUT: Unlike a standard gain control, this knob simultaneously attenuates bass and input gain at the front of the circuit. Turned fully clockwise, the control is bypassed for maximum fullness. Rolling it counter-clockwise gradually cuts the low end and thins out the signal, offering a tight, articulate response that handles driven amps and stacking beautifully.
The Fumble is available now directly from JHS Pedals and authorized dealers for $89/£89.99
JHS The Fumble FAQ
What is the difference between JHS The Fumble and the NOTADÜMBLË V1?
The clean side of the discontinued NOTADÜMBLË V1 DIY kit contained the exact JFET circuit found inside The Fumble. The Fumble is fully assembled, cheaper, and housed in a compact standalone enclosure.
Is The Fumble an overdrive pedal?
No. The Fumble is a dedicated JFET clean boost and tone sweetener. It does not generate heavy clipping or high-gain overdrive on its own, though it can be used to push your amplifier or other overdrive pedals into heavy distortion.
What are the power requirements for The Fumble?
The Fumble runs on standard 9V DC center-negative power and draws a remarkably low 5mA of current, making it highly compatible with virtually any pedalboard power supply.
Did Howard Dumble really steal the circuit?
Howard Dumble reverse-engineered a 1970s Barcus Berry piezo acoustic preamp and utilized its JFET architecture for his legendary “FET” channel switch. The Fumble is a faithful recreation of that exact JFET circuit architecture.
Verdict & Score
Pros
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Incredibly affordable boutique-quality JFET boost ($89 USD).
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Unique “Input” control tightens low-end and gain simultaneously.
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Authentic “Dumble FET” circuit tones without the $300,000 price tag.
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Incredibly low power draw (5mA) and small footprint.
Cons
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Will not provide heavy standalone overdrive if you are looking for solo lead tones.
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Those who already own the NOTADÜMBLË V1 already have this exact circuit.
Final Score: 8.3 / 10
The Verdict: The JHS Fumble is a masterclass in turning a corporate blunder into a guitar community win. It strips away the mythos of the “Dumble tone” to deliver an incredibly useful, unique, and wildly affordable tone-shaping tool that deserves a permanent spot on any serious pedalboard.
#JHS Pedals #The Fumble
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