The GUP Tech Poss'M is a dual pitch shifter pedal that GUP Tech describes as a "Synth/Bass/Guitar Polyphonic Pitch tweaker"1. Where a simple octave pedal gives you one shifted voice, the Poss'M carries two independent pitch shifting engines, each covering -1 to +1 octave, so a player can stack an octave up with an octave down, run two voices at the same interval, or set each one anywhere in between. Because it is polyphonic, it is built to track chords as well as single notes, on guitar, bass, or synth.
GUP Tech builds every pedal itself in Saguenay, Québec, Canada, including the Poss'M1. The standard pedal is offered in Orange and Purple color options, and both the standard version and the Douche Edition were listed as sold out as of late October 202612.
Two independent pitch shifters
The core of the pedal is its pair of pitch engines. GUP Tech lists "Two completely independent -1 to +1 Octave pitch shifting knobs (OCT 1 and OCT 2)"1. Each knob sets its own voice anywhere from one octave below the input to one octave above it, and neither is tied to the other's setting.
That layout is what separates the Poss'M from a basic octave pedal. With two voices you can, for example, run one engine an octave down for thickness and the other an octave up for a shimmer, or push both to the same setting for a stronger doubled effect. The maker's own framing is that this is the pitch "tweaker you need on your board," a tool for shaping shifted voices rather than switching a single fixed interval on and off1.
The controls
The control set is five knobs, and each one has a clear job:
| Control | What it does |
|---|---|
| OCT 1 | Sets the first pitch voice, -1 to +1 octave, independently |
| OCT 2 | Sets the second pitch voice, -1 to +1 octave, independently |
| Blend | Balances the two octave voices, from 100% OCT 1 to 100% OCT 2, through a 50/50 mix in the middle |
| Mix | Overall wet/dry balance, 0 to 100% wet |
| Volume | Output level, up to a +6dB boost |
All five controls come from GUP Tech's own product listing1.
The Blend knob is worth a closer look for anyone comparing dual-voice pedals. It does not set the wet/dry balance; it sets the balance between the two shifted voices. Full left is all OCT 1, full right is all OCT 2, and the center position gives an equal 50/50 mix of both1. The separate Mix knob then handles how much of that combined shifted signal sits against your dry tone, from fully dry to fully wet1. That two-stage arrangement means you can dial in the relationship between the two octaves first, then decide how far to submerge your original signal.
The Volume control adds up to +6dB of boost1, which is useful because pitch shifted layers can change how loud a part feels; a little push keeps the effect from sitting behind the dry signal.
Colors and the Douche Edition
Alongside the standard Orange and Purple versions, GUP Tech sells a Poss'M Pitch Shifter, Douche Edition2. The Douche Edition of the Poss'M carries the same feature set as the standard pedal, including the same five controls, the same 9V DC center negative power requirement, and the same 60mA draw2. Both versions were listed as sold out as of late October 202612.
The Poss'M takes 9V DC with a center negative plug only1. Check your power supply's polarity before plugging in, since a center positive supply will not work with this pedal.
Where it sits among pitch pedals
For a player weighing the Poss'M against other options in octave and pitch pedals, the deciding features are its two independent engines and its polyphonic tracking. A vintage-style octave unit such as GUP Tech's own BROctopus Green Ringer derives its octave from the input signal's own waveform and works best on single notes, while the Poss'M is a digital-style shifter meant to handle chords. The Blend and Mix knobs give it more of a studio-mixing character than a simple stomp-and-go octave fuzz, letting a player place two shifted voices precisely in the overall sound12.
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Questions
What power supply does the GUP Tech Poss'M need?
The Poss'M runs on 9V DC with a center negative plug only, as listed by GUP Tech. A standard center negative pedalboard power supply meets that requirement. The maker does not list battery operation, so plan on a power supply.
How much current does the Poss'M draw?
GUP Tech lists the power consumption of the Poss'M at 60mA. That is a modest draw, comparable to many analog drive pedals, and easy for a typical isolated pedalboard power supply to handle.
Where is the GUP Tech Poss'M made?
GUP Tech builds all of its pedals itself in Saguenay, Québec, Canada, including the Poss'M. It is a small Canadian builder rather than a mass manufacturer.
Can the Poss'M shift chords as well as single notes?
Yes. GUP Tech describes the Poss'M as a polyphonic pitch shifter for synth, bass, and guitar, so it is built to track more than one note at a time rather than only single-note lines.
Does the Poss'M have a blend between its two pitch shifters?
Yes. A Blend knob sets the balance between the two octave voices, from 100 percent of the first to 100 percent of the second, passing through a 50/50 mix in the middle. A separate mix knob controls the overall wet/dry balance.
Sources (2)
- Poss'M Pitch Shifter, GUP Tech (guptech.ca)
- Poss'M Pitch Shifter, GUP Tech (guptech.ca)
