The Colombo Audio Eruption is an overdrive/distortion pedal from Italian maker Colombo Audio Electronics, described by Delicious Audio as a "Plexi Overdrive/Distortion"1. It was designed and developed to get the guitar sound of the first six Van Halen albums, the one Eddie Van Halen used to call the brown sound1.
The pedal arrived as part of a wave of tribute gear: the death of Eddie Van Halen in October 2020 spurred a series of guitar gear releases dedicated to him, and the Eruption is Colombo Audio Electronics' way of paying tribute to the legend1.
What it does
The amp used on those Van Halen records was a Marshall 1959 Super Lead head, modded by adding a Variac transformer to reduce the voltage feeding it. The Eruption recreates that mod in a pedal. Its Variac control manages a virtual voltage: kept at minimum, the pedal holds the character of a stock Plexi, and as the control is raised it reduces the same frequencies an under-powered amp would, emulating the Variac physical phenomenon1.
That makes the Eruption a dual function pedal. Delicious Audio describes the two sides of it this way1:
"Eruption is therefore a dual function pedal: those who are fond of the original Plexi sound can keep the Variac control down"
With the Variac control down, the pedal delivers the typical Marshall historic sound with even more gain available; raising it recreates the brown sound of Eddie Van Halen, the tone the pedal was designed to capture from the first six Van Halen albums1.
In practice, the control splits the pedal into two distinct characters:
| Variac setting | What you get |
|---|---|
| Minimum | Stock Plexi character, the typical Marshall historic sound with even more gain available1 |
| Raised | The under-powered amp response of the Variac mod, aimed at the brown sound of the first six Van Halen albums1 |
Where it sits among Plexi-style pedals
Delicious Audio added the Eruption to its article on Plexi-style pedals in May 20211. Players comparing it with other drives in the same family can look at Colombo's own range: the Colombo Utopia Overdrive, the Colombo Audio Pulse Driver and the Southern Stalker, all from Colombo Audio Electronics. For a wider view of the category, see Overdrive Pedals and Distortion Pedals, or the Boss SD-1 vs Ibanez TS9 Tube Screamer comparison.
Videos
Brett Kingman
Luca Colombo
Luca Colombo
Questions
What is the Variac control on the Colombo Audio Eruption?
The Variac control manages a virtual voltage inside the pedal. At its minimum the Eruption keeps the character of a stock Marshall Plexi. As the control is raised it reduces frequencies the way an under-powered amp does, emulating the physical effect of a Variac transformer. That raised setting is aimed at the brown sound of the first six Van Halen albums, while the minimum setting suits players who want the typical historic Marshall sound with even more gain available.
Is the Colombo Audio Eruption an overdrive or a distortion?
It is described as both. Delicious Audio lists it as a Plexi Overdrive/Distortion and as a distortion pedal. It is a dual function design: with the Variac control down it delivers the typical Marshall historic sound with even more gain available, and with the control raised it recreates the brown sound associated with Eddie Van Halen.
Sources (1)
- Colombo Audio Eruption Plexi Overdrive/Distortion, Delicious Audio, 2021-05-06
