The Durandal Transparent Drive is based on the King Tone Blues Power, originally released in 2017.
Unlike the Duellist, there was no implication that it was based on any existing classic circuit. However, we traced one in 2022 and found that it’s nearly identical to a Timmy, with a few minor tweaks and some added options. The treble response can be adjusted with the “Edge” switch (edge, stock, glass), and an internal DIP switch has four different midrange positions.
King Tone was a bit sneaky in concealing this one: the PCB has a transistor with all three legs connected to ground, meaning it’s a decoy for people looking at gut shots trying to figure out what it’s based on. (The earliest versions of the Blues Power didn’t have this transistor.) There are also four diodes in the second op-amp stage that seem to be for clipping, but since this stage is unity gain, they have no effect. This could be another attempted decoy or just a design oversight.
The Durandal is a direct clone of the Blues Power… including the transistor and diodes, if you want to be in on the joke. However, these can be omitted entirely with no effect.