“The tonal character and responsiveness of all four pedals is indeed quite tubular”: Vox Valvenergy Fuel Injector, Tone Sculptor, Power Burst and Smooth Impact review

What is it?

Vox first introduced its Nutube technology in a series of micro amps back in 2017, followed by their first series of Valvenergy pedals featuring an all-analog signal path and Nutube tech in 2021.

Nutube involves a genuine miniature vacuum tube adapted from vacuum fluorescent display (VFD) technology to function like a traditional tube but with low-current and low-voltage specs.

The new second series of Vox Valvenergy pedals consists of the Fuel Injector Tube Overdrive, Power Burst Tube Booster, Smooth Impact Tube Compressor and Tone Sculptor Tube Preamp Equalizer.

As with the previous series, these Valvenergy pedals employ Nutube to provide the dynamic responsiveness and rich harmonic overtones of traditional tube technology but without bulky designs and maintenance issues.

Usability and sounds

Each Valvenergy pedal is housed in a sturdy metal case that’s slightly wider and taller than a Phase 90. Because of the higher than average power consumption, using a 9VDC pedalboard power supply is recommended but an easy-access battery compartment is also provided. A Link jack allows users to connect multiple pedals together and switch between them with one footswitch.

Controls are straightforward. The Fuel Injector overdrive pedal provides a typical three-knob (Level, Drive, Tone) configuration plus a Natural/Fat toggle switch.

The Power Burst booster offers a single Boost knob (about 20dB, but due to the character of the NuTube it will compress and distort at higher levels) plus a 3-position toggle with Treble, Natural and Middle settings.

Smooth Impact’s compressor controls consist of Output, Comp and Tube Gain knobs and a toggle with Vintage/Natural/Sag settings.

Tone Sculptor combines preamp overdrive and graphic EQ in a single box with six EQ sliders (100Hz, 250Hz, 570Hz, 800Hz, 2.2kHz and 5.6kHz) with 10dB boost/cut and a +/-12dB Level slider. All four pedals include an illuminated graphic waveform display instead of a typical on/off LED.

This feature is particularly helpful with the compressor as it shows how much the effect is adjusting the signal and decay, while on the other pedals it’s more of a novelty.

The overall tonal character and responsiveness of all four pedals is indeed quite tubular as promised. The Smooth Impact’s compression effects sound especially natural without any pumping or squashed textures.

Pick attack is articulate and notes sustain with impressive body without boosting noise. The overall character is more studio processor than typical stompbox compression.

The Tone Sculptor’s graphic EQ makes it perfect for players who want more control over dialing in lead tones than typical overdrive pedals offer.

The EQ bands are ideal for natural-sounding guitar tones with bass that sounds full but not flabby, mids with expressive voice-like qualities and treble that cuts without being harsh. Performance is noise-free.