The Asteria Preamp Drive Mk. II is a pedal that is based on the Catalinbread Formula No. 5 V2, which is an adaptation of the Fender Tweed Deluxe amplifier. The Formula No. 5 is known for its harmonically-rich breakup and the Asteria Mk. II replicates this sound.

The Formula No. 5 was originally released in 2011 and was traced by Aion FX in 2020. It replicates the quirks of the original Deluxe amp, including a tone control that has a diminishing effect as the gain is turned up. At maximum drive, there is almost no change across the sweep of the tone control.

The Asteria Mk. II blurs the line between a preamp and an overdrive pedal. It is very reactive to what comes before it, so it is best placed after other drive pedals but before modulation effects. However, it can also be used as a standalone overdrive pedal.

The Asteria Mk. II is similar to the original Formula No. 5, but there are enough differences that they are released as separate projects. The Formula 55 is a full redesign of the circuit from 2017 and is also available from Aion FX as the Asteria Mk. III.

The Formula No. 5 used 2N5457 JFETs, which are no longer available in through-hole format. However, the Asteria Mk. II provides extra pads if you want to use surface-mount JFETs (MMBF5457). Aion FX also offers pre-soldered MMBF5457s on adapter boards for those who find surface-mount parts intimidating.

The Asteria Mk. II is compatible with the 18V Voltage Doubler / Bypass module, which allows you to run the circuit at 18V without an external adapter. This higher voltage provides increased volume and clarity.

Summary created by AI from the original source.