The NRG Effects Gnawer is a distortion pedal built by NRG Effects, a small British builder run by Neil. It is a RAT-inspired circuit, but not a copy: it uses a NA5534P op-amp rather than the original RAT's chip, and it adds soft and hard clipping modes, a Sizzle boost and a range of cosmetic options12. Delicious Audio announced it in December 2023 as a RAT-inspired dual-channel overdrive1, and Guitar Pedal X reviewed the current version in July 2026 as "an evolved Rat-style Distortion with Soft and Hard clipping"2.
The pedal has been through changes. A previous version existed a little over two years before the one reviewed in 2026 and was significantly different, though Guitar Pedal X's reviewer felt the core gain stage carried over2. A 2024 mockup of a related Gnawer Full Fat Distortion showed a five-knob format with a "Plus" second channel acting as a combined gain and volume boost3.
An evolved RAT-style distortion
The Gnawer takes the RAT circuit as its starting point but departs from it in the parts that shape the sound. The NA5534P op-amp is a deliberate substitution for the original RAT's chip1. Where clipping is concerned, the pedal offers both soft and hard clipping paths, each with selectable diode configurations, where a stock RAT has a single fixed clipping arrangement2.
Delicious Audio noted one practical result when the pedal was announced: unlike original RATs and many of their variations, the Gnawer has a very usable range of tones also at lower gain1. For a player, that means the pedal can sit on a board as a lower-gain drive rather than only as a full distortion.
Guitar Pedal X's 2026 review was strongly positive about the current version:
"All the decisions he has made along the way - culminate in this exceptional evolved Rat-style Distortion"
The controls and clipping modes
The 5-knob edition reviewed in 2026 carries five knobs, two footswitches and a clipping mode selector2.
| Control | What it does |
|---|---|
| Loud (Output) | Sets the output level |
| Gain | Sets the amount of distortion |
| Treble | Sets the high-frequency content |
| Clipping Modes | Selects soft or hard clipping and the diode configuration |
| Sizzle! | Highs intensity and gain boost, on its own footswitch |
| Engage | On/Off footswitch for the pedal |
The clipping selector is the heart of the pedal's flexibility. Each path offers three diode arrangements, which change the character of the clipped waveform and the amount of headroom2.
| Path | Positions |
|---|---|
| SOFT | 2 x Diodes / Diode + LED / 2 x LEDs |
| HARD | 2 x Diodes / Diode + LED / 2 x Diodes |
The 2023 announcement described the pedal as dual-channel, with a Gnaw footswitch to switch between the two channels and a 3-way Hair switch adding two settings with extra headroom1. The 2026 edition replaces that arrangement with the Sizzle footswitch, which adds color-shifting LEDs along with the highs intensity and gain boost functions2.
Editions, enclosures and LED options
The Gnawer is available in two editions, differing in knob and footswitch count2.
| Edition | Knobs | Footswitches | Price |
|---|---|---|---|
| 5-Knob / 2-Footswitch | 5 | 2 (Engage + Sizzle) | £329 |
| 4-Knob / 1-Footswitch | 4 | 1 (Engage) | £289 |
Both prices are as reported in July 2026, in GBP as stated by the builder2.
The enclosure is a 1590B3, measuring 77 x 116mm, which sits between the common 125B and 1590BB sizes2. Two finishes are offered: black is stock, and Neil's Satin-Polished finish costs £10 extra2.
Each pedal is hand-wired, with a variety of status LED and internal wiring color schemes, and color scheme requests can be made when ordering2. The first production prototype, shown at the Norwich Fret Fest, had static red LEDs and red internal wiring; the production pedals add the color-shifting LEDs2. The stock main lens caps are smooth diffused ones, and the reviewer's own unit was the first color-shifting Gnawer built with a faceted crystal lens cap he sourced himself2.
The website listing was not fully active as of July 2026. Early orders go through the contact form rather than a standard checkout, and enclosure or color scheme requests should be made when ordering2.
Videos
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Pedal Experiments
Questions
How much does the NRG Effects Gnawer cost?
The 5-knob, 2-footswitch edition is £329, and a more stripped down 4-knob, 1-footswitch edition is £289, as reported by Guitar Pedal X in July 2026. The stock black enclosure is included; the Satin-Polished enclosure option costs £10 extra. Prices are in GBP as stated by the builder.
What op-amp does the Gnawer use?
The Gnawer is based on a NA5534P op-amp, not the op-amp used in the original RAT. Delicious Audio reported this when the pedal was announced in December 2023, describing the pedal as a RAT-inspired dual-channel overdrive by a small British builder.
What does the Sizzle footswitch do on the Gnawer?
Sizzle is a highs intensity and gain boost. On the 5-knob, 2-footswitch edition it gets its own footswitch, so you can kick in extra top-end bite and gain on the fly. The 4-knob, 1-footswitch edition drops this second footswitch.
How much current does the Gnawer draw?
It runs on 9V DC with a center negative plug and draws 30mA, as reported by Guitar Pedal X in July 2026. That is a modest draw, comparable to many analog distortion pedals.
How do I order an NRG Effects Gnawer?
As of July 2026 the website listing was not fully active, and the builder asked anyone wanting to place an early order to get in touch through the contact form. Enclosure and colour scheme requests, including LED and internal wiring colours, can be made when ordering.
Sources (3)
- New Pedal: NRG Effects Gnawer Distortion, Delicious Audio, 2023-12-15
- Guitar Pedal X, Guitar Pedal X, 2026-07-30
- Guitar Pedal X, Guitar Pedal X, 2024-08-30
