The OPFXS Twin Boost is a dual clean boost pedal from the Italian maker OPFXS. It combines two +24dB, clean, transparent analog boosts with digital control, so the audio path stays analog while the presets, channels and switching are handled digitally1. Guitar World reported the pedal's announcement in December 2023, describing it as a low-noise, high-output pedal that provides up to a 24dB push for driving tube amps, overdrives and distortions2.
Guitar Pedal X's review, by Stefan Karlsson, calls the core analog twin boosts "about as Clean / Transparent / Non-Colouring as you can get"1. For a player, that places it firmly in the boost pedals category: it raises level without shaping tone, whether that is to push an amp harder, lift a solo, or feed a second amplifier.
What it does
Guitar Pedal X's buying guide sums up the design as an "Ingenious digitally-controlled twin clean boost with multiple routing and deployment options, including split mode stereo" action, auto-swell, and step-up boost3. The two channels can run together or independently: the pedal offers bypassed or independent channels, with three presets per channel in Separate mode1.
The stereo side is central to the concept. Guitar World notes the pedal is named after its dual mono and stereo outputs, which allows gain boosts to be sent to different amplifiers2. Routing is cable-dependent: TRS cables enable Pre/Post Boost, separate pedals or amps, and an FX Loop Insert, while a mono input provides mono out only1.
Split-mode stereo routing, the FX loop insert and pre/post boosting all rely on TRS cabling. A plain mono cable in gives mono out only1.
The controls and presets
The front panel is deliberately simple, with the digital layer underneath. Guitar World describes the layout this way: "A control knob will do much of the manual dirty work, operating the gain and preset transition changes"2.
| Control | What it does |
|---|---|
| Control knob | Operates gain and preset transition changes2 |
| White Knob | Adjusts the +dB gain manually1 |
| F1, F2 and MIDI | Handle presets, channels, Joint/Separate operation and Tip/Ring selection1 |
| F2 (long press) | Toggles between Preset Mode and Gain Step Mode1 |
| Left Footswitch | Adjusts the gain step intervals1 |
Presets and gain steps work as follows:
- Three presets, numbered I to III, are available per channel, indicated by red LEDs under the white knob1.
- Presets can be saved and recalled via a footswitch2.
- In Gain Step Mode, gain steps use 1 to 24dB intervals, adjustable with the left footswitch1.
- A Slew Rate control provides a 0 to 99 transition timing scale for the gain step intervals, which is what drives the auto-swell behavior1.
For manual use, the gain can simply be set with the white knob, adjusting the +dB gain directly without touching the preset system1.
MIDI and integration
MIDI control covers the pedal's key functions, with the F1, F2 and MIDI controls handling presets, channels, Joint/Separate operation and Tip/Ring selection1. That makes the Twin Boost usable alongside MIDI pedals on a larger board, where its channels and presets can be changed remotely rather than only from the pedal's own switches.
Power
The Twin Boost takes a standard 9V plug, according to Guitar World's coverage2.
What reviewers said
Guitar Pedal X's Stefan Karlsson reviewed the pedal in December 2023 and gave it a strongly positive reading:
"Just a really smart, versatile, well engineered and thoroughly well thought out pedal."
The same review describes the overall design as a genuine innovation and first of its kind1. Guitar World's news coverage of the announcement frames it as a stereo-output analog boost with digital control, presets and MIDI at a starting price of €150, approximately $162/£1302.
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Questions
How much gain does the OPFXS Twin Boost add?
Each of the Twin Boost's two channels is a clean analog boost that pushes up to 24dB. Guitar World describes it as a low-noise, high-output pedal that provides up to a 24dB push for driving tube amps, overdrives and distortions. Guitar Pedal X's review calls the core analog twin boosts about as clean, transparent and non-colouring as you can get.
Does the OPFXS Twin Boost have MIDI?
Yes. Guitar Pedal X's review reports MIDI control over key functions, with the F1, F2 and MIDI controls handling presets, channels, Joint/Separate operation and Tip/Ring selection. That puts the Twin Boost among the digitally controlled options in the boost category rather than a simple set-and-forget stompbox.
Is the OPFXS Twin Boost stereo?
Yes. Guitar World describes the Twin Boost as a stereo-output pedal, named after its dual mono and stereo outputs, which allows gain boosts to be sent to different amplifiers. With TRS cabling it can also run pre and post boosts, feed separate pedals or amps, or sit in an effects loop insert.
What voltage does the OPFXS Twin Boost use?
The Twin Boost runs on a standard 9V power supply, according to Guitar World's coverage of the pedal's announcement. No battery option or current draw figure is given in the published coverage, so plan your supply accordingly.
How much does the OPFXS Twin Boost cost?
The OPFXS web store listed the Twin Boost at €150 and equivalent when Guitar Pedal X reviewed it in December 2023. Guitar World reported the launch price as starting at €150, approximately $162 or £130, at the time of the announcement.
Can the Twin Boost run in an effects loop?
Yes. Guitar Pedal X's review notes that TRS cables enable Pre/Post Boost, separate pedals or amps, and an FX Loop Insert. A mono input provides mono out only, so the loop and split routing options depend on using TRS cables.
Sources (3)
- Guitar Pedal X, Guitar Pedal X, 2023-12-04
- Is the OPFXS Twin Boost the future of boost pedals?, Guitar World, 2023-12-13
- Guitar Pedal X, Guitar Pedal X, 2023-12-16