The One Control Minimal Series BJF Buffer is a compact buffer pedal built to solve a problem every pedalboard player eventually meets: long cable runs and rows of true bypass pedals slowly eat the high end and strength of a guitar signal. One Control says Björn Juhl from BJFe designed the circuit specifically for the varied cable lengths and true bypass pedals found in a real signal chain, and the company packaged it in its small Minimal Series enclosure1.
One Control describes what the buffer does in practical terms: it amplifies the signal without changing the apparent volume or distortion, adding what the maker calls some toughness and strength to your sound1. In other words, it is not a boost or a tone shaper in the usual sense; it is a utility pedal that keeps the signal you already have intact across a board.
The Minimal Series BJF Buffer is listed as sold out on One Control's site as of 26 October 2026, as is the related One Control BJF Buffer Split12. The circuit itself remains available inside several other One Control products, covered below.
What the pedal does and how it is controlled
The BJF Buffer is a straightforward, always-on-style utility box with one notable control: a Phase Inversion switch. One Control explains that the switch is used to restore phase that may be inverted depending on the characteristics of your equipment, or to match the phase of other instruments1. That matters in stereo or two-amp setups, where an out-of-phase signal can thin out or cancel parts of your sound.
The maker's own description of the sound is worth quoting directly, since it frames what a buffer should and should not do:
"The BJF Buffer will help amplify the signal without changing the apparent volume or distortion, adding some toughness and strength to your sound."
One Control also calls the BJF Buffer one of its most natural-sounding circuits, with ultra-low noise output, and says it is installed in many of the company's switchers34.
Power: 9V center negative, 3mA
The pedal runs on a center negative DC9V adapter and draws only 3mA, which makes it a trivially light load for any pedalboard power supply1. There is no battery option: One Control states that batteries cannot be used1.
Because there is no battery compartment, the pedal needs a power supply from day one. At 3mA it can share an isolated output or a well-filtered daisy chain with other low-draw analog pedals without strain.
The same power spec, 9V DC center negative, runs through the whole family of One Control products that carry the BJF Buffer, including the Black Loop Deluxe, the White Loop, the Black Loop and the Silver Para Bass Buffer5647.
A Björn Juhl circuit used across One Control pedals
The BJF Buffer is not a one-off design. Björn Juhl, the Swedish designer behind BJFe, created it, and One Control describes him as one of the great amp and effects designers, noting the buffer was created at the request of many of the world's greatest guitarists8. In a 2023 interview published by One Control, the company explained how the circuit arrived:
"This in turn was brought to One Control both as a standalone pedal and featured in the loop switchers."
The same interview notes the BJF Buffer was One Control's first product: "We started with the BJF Buffer"9. Guitar World, covering the LX Tuner in 2022, likewise described its built-in buffer circuit as the BJF Buffer, designed by Björn Juhl, switchable on and off10.
The circuit now appears across a wide slice of the One Control range9:
| Product | What it is | How the BJF Buffer fits |
|---|---|---|
| Pedal Board Junction Box with BJF Buffer | Junction box with two inputs and two outputs | Buffer on/off via BUFFER/PASSIVE switch; 500kΩ input and 60Ω output impedance with buffer on3 |
| Black Loop Deluxe with BJF Buffer | Two-loop switcher | Built-in BJF Buffer at the input, switchable true bypass or buffered bypass5 |
| White Loop with BJF Buffer | Loop switcher | Switchable BJF Buffer on the input, can instantly cut the loop channel4 |
| Black Loop with BJF Buffer | Loop switcher with buffer and DC outs | Can operate without power when the input BJF Buffer is set to OFF, though the LEDs do not light6 |
| Mosquito Blender Expressio with BJF Buffer | Blender with buffer | BJF Buffer switch applies the buffer to the input part11 |
| Minimal Series Tuner MKII with BJF BUFFER | Pedal tuner with built-in buffer | Buffer can be active or passive; state shown on the display as ON or OFF8 |
| LX Tuner with BJF Buffer | Tuner with switchable buffer | Built-in BJF Buffer, switchable on and off10 |
| Silver Para Bass Buffer | Buffer for electric bass | A BJF Buffer variant optimized for the low end7 |
| TRI LOOP | Loop switcher | Listed with the BJF Buffer among its features12 |
Where a buffer fits on a pedalboard
A buffer's usual job is to sit early in the chain, after the guitar, so it can drive everything that follows. One Control's own answer to placement is the Pedal Board Junction Box with BJF Buffer, which puts the input and output jacks on the top of the enclosure so it can sit at the edge of a board without wasting pedal space3. That box also shows how the company thinks about flexibility: when the buffer is off, both of its A and B terminals can be connected from any direction, and when it is on, the A side always enters from BUFFER IN and exits from BUFFER OUT3.
For players comparing standalone buffers, the Minimal Series BJF Buffer sits alongside small-format options like the JHS Pedals Little Black Buffer, the TC Electronic Bonafide Buffer and the MOSKY PURE BUFFER. Its distinguishing features are the designer's name behind the circuit and the phase inversion switch, which is not common on compact buffers; the Saturnworks buffer with phase inversion switch is one of the few direct parallels.
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Questions
Who designed the One Control BJF Buffer?
Björn Juhl of BJFe designed the BJF Buffer. One Control says he created it to deal with the varied cable lengths and true bypass pedals found in a modern signal chain. The circuit was One Control's first product and now appears both as this standalone pedal and built into many of the company's loop switchers and other utility pedals.
Does the One Control BJF Buffer change your tone?
One Control describes it as amplifying the signal without changing the apparent volume or distortion, adding toughness and strength to the sound rather than a distinct tonal color. The company calls the BJF Buffer one of the most natural-sounding buffers it makes, with ultra-low noise output. As with any buffer, what you hear is the recovery of signal lost to long cables.
Can the One Control BJF Buffer run on a battery?
No. One Control states plainly that batteries cannot be used with the Minimal Series BJF Buffer. It requires a center negative DC9V adapter, drawing only 3mA, so it is an easy load for a standard pedalboard power supply but not a candidate for battery power.
Where should a buffer go on a pedalboard?
A buffer is normally placed at the start of the chain, right after the guitar, so it drives the long run of cables and true bypass pedals that follows. One Control's own take on placement is its Pedal Board Junction Box with BJF Buffer, which puts the buffer in a small box with jacks on top of the enclosure so it can sit at the edge of a board without wasting pedal space.
Is the One Control BJF Buffer discontinued?
The Minimal Series BJF Buffer is listed as sold out on One Control's site as of late October 2026, as is the related BJF Buffer Split. One Control has not stated that the pedal is discontinued, but it is currently unavailable direct from the maker. The BJF Buffer circuit itself lives on in other One Control products.
Which One Control pedals have the BJF buffer built in?
The BJF Buffer appears across the One Control range, including the Pedal Board Junction Box with BJF Buffer, the Black Loop and Black Loop Deluxe, the White Loop, the Mosquito Blender Expressio, the Minimal Series Tuner MKII, the LX Tuner, the Silver Para Bass Buffer and the TRI LOOP.
Sources (12)
- Minimal Series BJF Buffer (OC-M-BUF), One Control USA
- Minimal Series BJF Buffer Split (OC-M-BJBUF), One Control USA
- Minimal Series Pedal Board Junction Box with BJF Buffer (OC-M-JBBUF), One Control USA
- Minimal Series White Loop with BJF Buffer (OC-M-WL2), One Control USA
- Minimal Series Black Loop Deluxe with BJF Buffer (OC-M-BLDLX), One Control USA
- Minimal Series Black Loop with BJF Buffer (OC-M-BL2), One Control USA
- Minimal Series Silver Para Bass Buffer (OC-M-SPBB), One Control USA
- Minimal Series Tuner MKII with BJF BUFFER (OC-M-PT2), One Control USA
- Interview with the Legend, Björn Juhl from BJFE/One Control, One Control USA, 2023-09
- One Control expands its pedal lineup with the all-new LX Tuner with BJF Buffer, Guitar World, 2022-07-07
- Minimal Series Mosquito Blender Expressio with BJF Buffer (OC-M-MBEXP), One Control USA
- Minimal Series TRI LOOP (OC-M-TL), One Control USA
