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Gladiator Dual Drive

Based On
King Tone Duellist
Effect Type
Dual-channel overdrive
Build Difficulty
Project Summary
A popular dual-channel overdrive first released in 2015 that combines a stripped-down Tube Screamer with a hot-rodded Bluesbreaker.
Gladiator Dual Drive printed circuit board

Printed Circuit Board

What's included?
PCB only. Build instructions and parts list can be viewed or downloaded from this page.


In stock

Complete Kit

Not yet available.
Kits are developed based on interest, so if you’d like to see one for this project, let us know.
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Project overview

The Gladiator Dual Overdrive is based on the King Tone Duellist, a highly prized dual pedal first released in 2015 consisting of the “String Singer” for side A and the “Heavy Hand” for side B. The Duellist was traced by Aion FX in 2022.

The String Singer is based on a stripped-down Tube Screamer with input & output buffers removed. The circuit is highly modified, so the EQ and clipping will sound drastically different from the classic Ibanez circuit, but that was the source at least. This half of the circuit was released in single-pedal format as the Soloist, available from Aion FX as the Gladius.

The Heavy Hand is based on the Marshall Bluesbreaker, but again it has been heavily modified from the original circuit—so it may remind you of it, but it’s not going to sound quite the same. This half of the was also released as a single pedal called the Heavyhand, available from Aion FX as the Xiphos.

Each side also has an external “EQ” toggle switch to select between different EQ voicings, as well as two internal DIP switches for fat EQ and asymmetrical clipping (side A) or and asymmetrical clipping and hard clipping (side B).

The Gladiator simplifies the send/return functionality of the original unit by including 4 jacks by default. The send & return now have their own jacks that automatically short together if nothing is plugged in. Otherwise, the Gladiator is a direct clone of the Duellist based on our own trace. Details are available in the tracing journal.