The GUPtech Bass Bone is an overdrive-preamp for bass, made by GUPtech in Saguenay, Québec, Canada1. Its circuit is inspired by the Darkglass Microtubes B3K, a bass overdrive pedal that Darkglass aimed at "a perfect combination of brutality and clarity"2. GUPtech puts it plainly on the product page:
"Inspired by the incredible work around the Darkglass B3K, this overdrive-preamp is the perfect new friend to your bass"
The Bass Bone is a bass preamp/overdrive from GUPtech. It sits in the overdrive and preamp families as of late October 20261.
The Darkglass B3K connection
The pedal the Bass Bone draws on, the Darkglass Microtubes B3K, is a compact CMOS-based bass overdrive pedal3. No Treble covered it as an overdrive/distortion pedal for bass in November 20104, and when Darkglass updated the pedal to V2 in 2017, MusicRadar described it as a "bass overdrive with a transparent sound"5. A Pedal of the Day review by Max F. found that "The B3K Overdrive has simple and intuitive controls for sculpting a wide range of bass tones"6.
That lineage matters for a bass player comparing circuits: the B3K's approach of blending a driven signal with the clean bass tone is the design the Bass Bone builds on, and GUPtech carries it into a hand-built pedal from a small Canadian workshop17.
Controls and modes
The Bass Bone keeps its control set small. GUPtech describes two knobs and a set of voicing modes1:
| Control | What it does |
|---|---|
| Level knob | Controls the driven signal1 |
| Blend knob | Mixes from 0 to 100% of the pedal's dirt with your clean tone1 |
The blend knob is the heart of the design for bass: because it mixes your clean low end back in, you can push the driven signal hard without losing the fundamental that keeps a bass sounding like a bass1.
The pedal also offers three Attack and Grunt modes1. These are voicing switches for the driven signal, in the spirit of the B3K's mode switches, letting you shift the character of the dirt rather than just its amount. GUPtech's page lists the modes without breaking down each one individually.
Editions and versions
The Bass Bone has shipped in a few enclosure treatments, all with the same circuit891:
| Edition | Finish | Circuit |
|---|---|---|
| Bass Bone | Black | Original1 |
| Douche edition | Purple | Exact same circuit, more limited run8 |
| Gold Rush Edition | Gold | Exact same circuit as the original, in a unique gold box9 |
GUPtech says of the Douche edition: "As for all our other douche edition, this is the exact same circuit but in a more limited run"8. The Gold Rush Edition is the same idea: "Exactly the same circuit as the original GUPtech Bass Bone, in a unique Gold box"9. The Gold Rush Edition is sold out as of late October 20269.
The limited editions differ only in finish and run size. If you are comparing a used Douche or Gold Rush unit against the standard black Bass Bone, the circuit inside is the same.
Power and build
The Bass Bone runs on 9V DC with a center negative plug and draws 19mA1. That current draw is low enough that it can share a typical 9V pedalboard supply with other center negative pedals. All GUPtech pedals, the Bass Bone included, are made by the company itself in Saguenay, Québec, Canada1.
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Questions
What is the GUPtech Bass Bone based on?
The Bass Bone is an overdrive-preamp for bass whose circuit is inspired by the Darkglass Microtubes B3K. GUPtech describes it as an overdrive-preamp built around the work done on that pedal. It grew out of the company's Lab #26 circuit, which reached production as the Bass Bone in February 2021.
What do the Attack and Grunt modes do?
GUPtech lists three Attack and Grunt modes on the Bass Bone. These are the pedal's voicing modes, carried over from the Darkglass B3K design it is based on, letting you shift the character of the driven signal. The maker's page does not break down each mode individually.
What power does the Bass Bone need?
The Bass Bone runs on 9V DC with a center negative plug, and draws 19mA. That is low enough to share a standard pedalboard power supply with other 9V center negative pedals.
Where is the GUPtech Bass Bone made?
GUPtech makes all of its pedals itself in Saguenay, Québec, Canada. The Bass Bone is built there alongside the rest of the company's range.
What is the Bass Bone Gold Rush Edition?
The Gold Rush Edition is a limited version of the Bass Bone with exactly the same circuit as the original, housed in a unique gold enclosure. It is sold out as of late October 2026. There is also a Douche edition, a purple limited run with the same circuit.
Sources (9)
- GUPtech Bass Bone, GUPtech
- Microtubes B3K V2, Darkglass
- Microtubes B3K v1 by Darkglass Electronics, RockBoard (PedalPedia), 2026
- Gear Watch: Darkglass Electronics Microtubes B3K Overdrive Pedal, No Treble (www.notreble.com), 2010-11-05
- Darkglass's bass drive pedals get a boost as B3K and B7K are updated to version 2, MusicRadar, 2017-10-19
- Guest Reviewer Fridays: Darkglass Electronics Microtubes B3K Bass Overdrive, Pedal of the Day (pedal-of-the-day.com), 2016-08-26
- Surprise Pedal - Batch #6 - Bass Player Edition (Mystery batch), guptech.ca
- Bass Bone Douche edition, GUPtech (guptech.ca)
- Bass Bone, guptech.ca
