Artemis Mk. IIPreamp Drive

From the vendor

An updated adaptation of the Ampeg SVT, a legendary high-powered bass amplifier that first appeared in 1969. It uses cascaded mu-amp stages in place of tubes for amp-like tone in a small box.

The Artemis Preamp Drive Mk. II is an adaptation of the second version of the Catalinbread SFT, based on the legendary Ampeg SVT bass amplifiers. It was originally released in 2016. While the SVT was a bass amp, this circuit is suitable for bass or guitar.

Like several other Catalinbread pedals, this circuit blurs the line between a preamp and an overdrive. Like a true preamplifier, it’s very reactive to what comes before it, so it’s best placed after other drive pedals but before modulation. However, it also generates more than enough drive on its own and can be used as a standalone overdrive pedal just like any other.

The first version of the SFT was released in 2009. While both circuits are voiced with the same Ampeg SVT amplifiers as a reference, the two circuits are very different. The V2 also includes the “Stones/Stoner” switch, which re-voices the tone and increases the gain so it borders on fuzz territory.

The SFT V2 uses MPF4393 JFETs, which are no longer produced. Aion FX sells the original MPF4393s in sets of 6, the quantity needed for this circuit. The PCB also has an extra pad so that surface-mount JFETs can be used (part number MMBF4393), which are still in production and perform identically to those used in Catalinbread pedals. See documentation for more details.

Note: This project uses a type of capacitor that has been temporarily discontinued by WIMA. Please see our news article about the issue and the substitution spreadsheet for project-specific recommendations. We are stocking a limited supply in the mean time. The build document has not yet been updated to reflect this.