Waldorf Blofeld knob-per-function controller

Front view
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.

Close view Close view
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.
w/ Keylab w/ Keylab
Paired with an Arturia Keylab mk2 for the ultimate sound design experience.
w/ Blofeld Close view
w/ Blofeld w/ Blofeld
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.
Parts Assembly Module
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 Back view
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.