Waldorf Blofeld knob-per-function controller

Some 130 knobs & sliders, almost 60 buttons and switches.

The Waldorf Blofeld is a brilliant device with an extremely flexible sound engine, but navigating it's interface gets tiring. I designed & built a custom controller which turned it into a proper knob-per-function synthesizer with up to ~16 voice polyphony - an extreme rarity, and a joy to play with.

All Blofeld sound parameters are mapped to unique sliders or knobs, making them instantly available. The built-in display shows last moved value, which aids in precise inputs.

On some occasions, I merged some inputs into one knob where it made sense (e.g. glide on/off + glide mode). Arpeggiator params are unavailable, as that alone would take another 30% of space, and I prefer an external sequencer anyway.

Modulation sources and mod matrix are edited by pressing and holding the relevant slot button (+ source or destination buttons) and entering selection with the big slider on the control module.

The controller also features a "sync" mode, where it queries the Blofeld for current params and then guides the user, knob-by-knob, slider-by-slider, which inputs must be moved in order to get their positions in sync with current Blofeld settings. This allows for getting an overview of a sound recalled from Blofeld's memory simply by looking at knob positions after syncing.

In the future, I intend to document my design decisions, production costs, other challenges, and what I've learned in the process.

Selector knobs are annotated with available options, while continuous inputs use a scale with key values highlighted.	The display shows moved parameter values so that I can keep my eyes on the board.

Paired with an Arturia Keylab mk2 for the ultimate sound design experience.

Alongside my Blofeld. The board measures ~59x24cm, so it isn't small (hand for scale) - but that's unavoidable with the number of params on the Blofeld. I didn't go for tiny knobs and ensured comfortable spacing between them to make precise input effortless.

All components that make up a single module.	Assembled board for a filter module. JLCPCB's circuit board production quality vastly exceeded my expectations.	Completed module. All modules use the standard Eurorack dimensions, and will fit any Eurorack case. The one I used is a 114HP, 2x3U frame from ModularSynthLab.

Module layers are (bottom-up): 1.6mm PCB, 10mm gap, 1mm laser-cut stainless steel plate, printed paper with labels, thick plastic foil for shine and protection.	Modular design allowed me to save a lot in production costs and it lets me rearrange modules at will, but it results in this connection mess.

^{The Waldorf and Blofeld logos are property of Waldorf Music GmbH. Neither this project nor its author are endorsed by or affilated with Waldorf Music GmbH.}