The GUP Tech Volume Box is a small passive volume control made by GUP Tech, a pedal builder based in Saguenay, Quebec, Canada. It is designed to sit either in the FX loop of your amp or in front of it, adding a volume or master volume control where the amp does not have one. Because it is built entirely from passive parts, it needs no power at all: no battery, no supply tap, nothing to plug in1.
What it does
The Volume Box answers a simple problem: an amp with no master volume, or an FX loop with no level control, leaves you stuck with whatever the amp's own knobs give you. GUP Tech describes it as a way to "Add a volume, or master volume to an amp"1.
"Add a volume, or master volume to an amp"
Where you put it changes what it does:
- In the FX loop: it works as a master volume, letting you push the amp's preamp harder while setting the final level with the box1
- In front of the amp: it works as an ordinary passive volume control1
The circuit is a single 100kA potentiometer in a 1590A enclosure, so it takes up very little room on a board or on top of an amp1. It sits alongside other compact passive volume options such as the Bright Onion Pedals Bright Onion Micro Volume Control and the Vein-Tap.com Leech, and differs from rocker or treadle units like the Ernie Ball Mono Volume Pedal in being a set-and-forget knob rather than a foot-operated pedal.
What it is not
GUP Tech's own warning: "This ain't a power attenuator, installing this device between your amp Speaker Out and a Cab will surely destroy something"1.
That distinction matters. A power attenuator handles the speaker-level output of a tube amp's output transformer; a passive line-level box like this one does not. Keep it in the FX loop, in front of the amp, or in a low-level signal path, and never in the speaker line1.
Specifications and options
| Specification | Detail |
|---|---|
| Type | Passive volume box1 |
| Control | 100kA potentiometer1 |
| Enclosure | 1590A1 |
| Power | None, completely passive1 |
| Made in | Saguenay, Quebec, Canada1 |
The maker's page lists five color options, all built the same way:
| Color |
|---|
| Silver |
| Army Green |
| Red |
| Orange |
| Matte Orange |
The choice is purely cosmetic: every version uses the same 1590A enclosure and 100kA potentiometer1.
Availability
GUP Tech states that all of its pedals are made by the company in Saguenay, Quebec, Canada, and pickup is available at the GUP Tech shop there, usually ready within 24 hours1.
A closely related design, the Asheville Guitar Pedals Master Volume Box Attenuator, was reviewed on Pedal of the Day in May 2024, where the reviewer called it "an extremely useful piece of gear for any FX Loop-equipped tube amplifier"2.
Questions
Does the GUP Tech Volume Box need power?
No. GUP Tech describes the Volume Box as built from completely passive parts, so no power is required. There is no battery or power supply to worry about, and it will not add to the current draw on your pedalboard supply. You simply patch it in where you want the volume control and turn the knob.
Can I use the GUP Tech Volume Box as a master volume?
Yes. GUP Tech says the box can add a volume, or master volume, to an amp. Placed in the FX loop of an amp, it works as a master volume, letting you run the amp's front end harder while bringing the overall level down. A similar approach is reviewed on Pedal of the Day as useful for FX loop-equipped tube amplifiers.
Can I put it between my amp and cabinet?
No. GUP Tech is explicit about this: the Volume Box is not a power attenuator, and the maker warns that installing it between your amp's speaker output and a cabinet will surely destroy something. Speaker-level signals need a proper power attenuator, not a passive line-level volume box.
What colors does the GUP Tech Volume Box come in?
The maker's product page lists five color options: Silver, Army Green, Red, Orange and Matte Orange. All use the same 1590A enclosure and 100kA potentiometer, so the choice is purely cosmetic.
Where is the GUP Tech Volume Box made?
GUP Tech states that all of its pedals are made by the company in Saguenay, Quebec, Canada. The product page also notes that pickup is available at the GUP Tech shop in Saguenay, usually ready within 24 hours.
Sources (2)
- Volume Box, GUP Tech (guptech.ca)
- Asheville Guitar Pedals Master Volume Box Attenuator, Pedal of the Day, 2024-05-14
