The GUPtech Mad Chiou Scott Bynoe Artist edition is a dual boost pedal from GUPtech, the Québec-based builder of the pPTSD, the Slime Mid-Boost and the FrAG Boost. It puts two of the company's classic Boost-EQ pedals, the GrindR and the Le Chiou, into one enclosure, and GUPtech describes the result as "a two-in-one boost unit for your high gain amp"1. The artist edition was announced on 20 June 2021 and carries the same boost power as the Original Mad Chiou, in a pink enclosure with Scott Bynoe's signature on the side and a special design1.
The Scott Bynoe Artist edition is listed as sold out on GUPtech's site as of 26 October 20261. The standard Mad Chiou, with the same circuitry in Dark Green, Green or Light Blue, is listed as re-stocking soon2.
Two boost-EQ pedals in one box
The Mad Chiou is, in GUPtech's words, "a dual pedal of our classic GrindR and Le Chiou, both Boost-EQ pedal"1. Each side is its own boost-EQ circuit with its own footswitch, so the pedal can serve as two independent boosts on one board, or both sides can be used together into a high gain amp1.
The two sides do different jobs:
- Left side, Le Chiou: a bypassable 3-band EQ with a Tight knob, which GUPtech says offers "more volume you'll ever need"1. The standalone version of this circuit is the Le Chiou EQ-Boost.
- Right side, GrindR: an EQ boost that GUPtech describes as "a 3-in-one based on the TC integrated preamp with the Grind/33 EQ high pass filter at the flick of a toggle"1. GUPtech also builds the GrindR circuit in artist and special editions of its own, such as the GrindR Derryl Vi Artist edition and the GrindR Plem Edition.
The toggle on the GrindR side selects between two flavors of high-pass filter. Delicious Audio's Paolo De Gregorio, writing about the Mad Chiou in August 2022, named them "Grind" or the "33"3.
Power and practicalities
The Mad Chiou runs on 9Vdc center negative and draws 61mA2. GUPtech's own warning on the product page is blunt: "Anything higher will blow some stuff"1. In practice that means a standard 9V center-negative supply, and at 61mA it is worth checking the per-output rating of a daisy-chain supply before sharing an outlet with other pedals.
The artist edition and the standard Mad Chiou
The Scott Bynoe edition is one of GUPtech's artist editions, named for Scott Bynoe, whose signature appears on the side of the pink enclosure1. It shares its boost power with the Original Mad Chiou; the differences are cosmetic1. The standard Mad Chiou comes in Dark Green, Green and Light Blue color styles2.
| Scott Bynoe Artist edition | Standard Mad Chiou | |
|---|---|---|
| Circuit | GrindR + Le Chiou, same boost power as Original Mad Chiou1 | GrindR + Le Chiou1 |
| Enclosure | Pink, Scott's signature on the side, special design1 | Dark Green, Green or Light Blue2 |
| Status | Sold out1 | Re-stocking soon2 |
| Power | 9Vdc center negative, 61mA1 | 9Vdc center negative, 61mA1 |
Where it sits on a board
As a boost-EQ pair, the Mad Chiou covers ground that players usually split across two pedals: a shaping EQ side for scooping, tightening or adding body, and a GrindR side for pushing an amp with a high-pass filter option. Players who want either half on its own can look at the Le Chiou EQ-Boost or the GrindR editions, and GUPtech's Peeps Clean Boost covers the simpler single-purpose boost role123.
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Questions
What is the GUPtech Mad Chiou?
The Mad Chiou is a dual pedal from GUPtech that combines two of the company's classic Boost-EQ pedals, the GrindR and the Le Chiou, in a single enclosure. GUPtech describes the result as a two-in-one boost unit for a high gain amp. The left side carries the Le Chiou with its bypassable 3-band EQ, and the right side carries the GrindR EQ boost based on the TC integrated preamp.
Is the Scott Bynoe edition still available?
No. GUPtech's product page for the Mad Chiou Scott Bynoe Artist edition lists it as sold out as of 26 October 2026. The standard Mad Chiou, which has the same boost circuitry in different colors, is listed as re-stocking soon on GUPtech's site.
What does the toggle on the GrindR side do?
The toggle on the GrindR side switches between two flavors of high-pass filter, which Delicious Audio's Paolo De Gregorio describes as the Grind and the 33. GUPtech describes the GrindR side as a 3-in-one based on the TC integrated preamp, with the Grind/33 EQ high-pass filter available at the flick of a toggle.
Where is GUPtech based?
GUPtech builds its pedals in Saguenay, Québec, Canada. The company states on its product pages that all of its pedals are made by them there.
What power supply does the Mad Chiou need?
The Mad Chiou runs on 9Vdc center negative and draws 61mA. GUPtech warns that anything higher than 9V will blow some stuff, so a standard 9V center-negative supply is the only safe choice, and the 61mA draw is worth checking against your supply's per-output rating.
Sources (3)
- Mad Chiou Scott Bynoe Artist edition, GUPtech (guptech.ca)
- Mad Chiou, GUP Tech
- GUP Tech Mad Chiou Double Boost + EQ, Delicious Audio, 2022-08-02
