The Gamechanger Audio PLASMA Rack is a high voltage distortion unit in a 1U rack format. Instead of clipping your signal with LEDs, transistors or vacuum tubes, it converts the instrument's signal into a rapid series of high-voltage electric discharges inside a xenon-filled tube, up to 5500 volts, which are then picked up by an electromagnetic receiver and turned back into an audio-level signal12. The result, as the maker describes it, is a large amount of non-linear harmonic saturation with extremely rich and responsive attacks, bringing out screeching sharp overtones and harmonics1.
It is the rack-mounted sibling of the Gamechanger Audio PLASMA pedal, taking the same xenon-tube concept into a studio and stage unit with balanced I/O, three effects loops, a Baxandall EQ and full MIDI control13. Signal processing is fully analog, but the parameters can be digitally controlled1. It is made in Riga, Latvia1.
How the xenon tube distortion works
Most distortion pedals clip the signal with diodes, transistors or op-amps. The PLASMA Rack takes a different route: a high voltage step-up flyback transformer turns the instrument's signal into a rapid series of electric discharges in a xenon tube, and a specially designed electromagnetic receiver converts those discharges back into an audio-level signal2. Delicious Audio describes the pedal version's approach the same way: instead of LED circuits, transistors or vacuum tubes, the signal is transformed into continuous high-voltage discharges within a xenon-filled tube3. MusicRadar's reviewer similarly notes that the core distortion sound comes from clipping caused by high-voltage discharges as the signal runs through the tube5.
The level of distortion is controlled with two front-panel knobs: INPUT GAIN and VOLTAGE1. Two additional circuits shape the character:
- OVERSATURE: overloads the tube, adds upper harmonics and changes the dynamic response1.
- SUSTAINER: lets you dial in sputtery, broken sounds without losing sustain1.
Modulating the xenon lamp itself creates tremolo and ring modulation sounds, and the maker lists a clean gate effect among its capabilities1. The tremolo rate range runs from 0.85 to 2600 Hz4.
Controls and EQ
The EQ is a Baxandall type, MIDI controllable2. Its bands:
| Band | Frequency | Range | Filter type |
|---|---|---|---|
| Low | 10 Hz | -20 to 20 dB | Low-pass shelving4 |
| Mid | 600 Hz | -6 to 6 dB | 2 |
| High | 20 kHz | -10 to 10 dB | High-pass shelving2 |
The preamp gain range is -26 to +12 dB2. The EQ gives the player a low-pass shelving filter at 10 Hz with a -20 to 20 dB range, a mid control at 600 Hz with a -6 to 6 dB range, and a tremolo rate range of 0.85 to 2600 Hz24.
Inputs, outputs and effects loops
The PLASMA Rack has balanced and unbalanced I/O and works with both instrument and line level signals1. There are three effect loops placed in different parts of the signal chain, which also work with instrument and line level signals1.
| Connection | Details |
|---|---|
| Unbalanced input | Tip-sleeve 1/4" jack, 1MΩ impedance, instrument input, RF filtered, max input level +11 dBu, true bypass to unbalanced output2 |
| Balanced input | Combo connector, female XLR and TRS 1/4" (pin 2 and tip hot), 4.38 kΩ impedance (1.5 kΩ with PAD on), mic/line, RF filtered, max input level +17 dBu (+37 dBu with PAD), true bypass to balanced output2 |
| Unbalanced output | Tip-sleeve 1/4" jack, 220Ω impedance, max output level +7 dBu2 |
| Balanced output | Male XLR (pin 2 hot), 200Ω impedance, max output level +10 dBu2 |
| FX loop sends 1-3 | 100Ω impedance, max output level +12 dBu (line) or -6 dBu (instrument)2 |
| FX loop returns 1-3 | Max output level +14 dBu2 |
The PAD switch gives -20 dB of attenuation on the balanced input only4. The maker's support documentation confirms the output layout: one unbalanced output and one balanced output6.
Because it accepts line-level and balanced signals, the unit is not limited to guitar. Performer Mag's review found it works well with synths and drum machines, and concluded the rack is best suited to synth, drum machine and recording users7.
MIDI, presets and expression
The PLASMA Rack has full MIDI implementation, with each parameter controllable by MIDI CC and PC messages1. There are 8 user preset slots plus a default boot-up preset and settings1. The expression pedal input can be rerouted to any parameter and saved on a global or preset basis1.
The unit is mono, but it is designed to work in a master/slave configuration for stereo signal processing1, and the maker's artist pages show a Plasma Rack stereo setup in use8.
Power and specifications
The PLASMA Rack runs on mains power rather than a pedalboard power supply. It uses a universal switch-mode power supply accepting 90 to 245 VAC at 50/60 Hz, and ships with a power cable suited to your region26.
| Specification | Value |
|---|---|
| Rack spaces | 1U2 |
| Dimensions | 440mm (W) x 255mm (D) x 40mm (H)2 |
| Weight | 4.1 kg2 |
| Power consumption | 60 W4 |
| Frequency response | 30 Hz to 20 kHz (±3 dB)4 |
| Operating temperature | 0º to 40º C4 |
| Warranty | Lifetime2 |
Price and buying
The list price is $1,499 USD, as given on the maker's product page in February 20262; the maker's shop page also lists 1,238.00 EUR1. For US orders the maker charges no sales tax, but 2.7% customs duties apply on arrival; EU orders have VAT added unless an EU-VAT number is supplied4.
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Questions
How much does the Gamechanger Audio Plasma Rack cost?
The list price is $1,499 USD, as given on Gamechanger Audio's product page in February 2026. The maker also lists a price of 1,238.00 EUR on its shop page. US orders carry no sales tax from the maker, but 2.7% customs duties apply on arrival.
Can the Plasma Rack run in stereo?
It is a mono unit, but Gamechanger Audio designed it to work in a master/slave configuration for stereo signal processing. The maker's artist pages show a Plasma Rack stereo setup in use, and full MIDI implementation makes syncing two units practical.
Does the Plasma Rack work with synths and drum machines?
Yes. It has balanced and unbalanced I/O and works with both instrument and line level signals, and Performer Mag's reviewer found it works well with synths and drum machines, concluding it is best suited to synth, drum machine and recording users.
Is the Plasma Rack true bypass?
Yes. The unbalanced input is true bypass to the unbalanced output, and the balanced input is true bypass to the balanced output. So both input paths have a true bypass route when the unit is disengaged.
How many volts does the Plasma Rack use?
The discharges inside the xenon tube reach up to 5500 volts. The unit itself runs from a universal switch-mode power supply accepting 90 to 245 VAC at 50/60 Hz, with 60 W power consumption, and ships with a power cable suited to your region.
Sources (8)
- PLASMA RACK, Gamechanger Audio, 2026-09-23
- PLASMA Rack, Gamechanger Audio, 2026-02-16
- Gamechanger Audio Plasma Distortion, Delicious Audio, 2023-07-11
- PLASMA Rack, Gamechanger Audio, 2025-02-12
- 5 fuzz pedals guitar players need to try, MusicRadar, 2021-03-16
- PLASMA Rack Support, Gamechanger Audio, 2025-11-12
- Gamechanger Audio Plasma Rack REVIEW, Performer Mag, 2020-02-04
- Tommy Simpson, Gamechanger Audio, 2022-07-07
