"Inspired by the Trainwreck Express amplifier (built by the late Ken Fischer), the TWE-1 is solid-state pedal designed to emulate the touch-responsiveness and clean-to-overdriven range you get from a high-grade tube amp. Along with Volume, Hi Cut, and Gain controls, the pedal has 3-position Cab switch (4x12, 2x12, off), a Presence switch that provides three levels of high-frequency boost (post OD), a Voice switch (Traditional and Modern British), and a bypassable Brite switch that provides two levels of high-frequency boost (pre OD).
The TWE-1 with its Gain at noon or higher responded in an amp-like way to changes in guitar volume and picking strength, delivering everything from gritty cleans to richly saturated distortion textures. Thanks to its strong output, the TWE-1 is suitable for clean boosting too. All good stuff, but the standout feature of the TWE-1 is its powerful tone-shaping ability. The Hi-Cut knob attenuates treble when turned clockwise, and the Brite switch makes it easy to get the appropriate sparkle with humbuckers or single-coils. The Cab switch beefs up the low-end significantly in the 4x12 position (I felt the 2x12 setting sounded best with my Deluxe), and the Voice switch lets you choose between a thicker tone in the “M” position or one with more upper-midrange emphasis in the “T” setting. The Presence switch set to Hi restores shimmer when the Hi Cut control is turned up (a cool sound in itself), and between all of these functions, the TWE-1 certainly answers the needs of players who want a compact OD pedal with exceptional sound and flexibility."
The layout should fit in a 125B size box.
You can find Bugg's schematic and easier-to-build pcb on his website here.
This is a buffered effect. Follow the layout to connect the footswitch.