Getting Started with the Chromaplane!
The Chromaplane is an electromagnetic synthesizer designed by Passepartout Duo, now available through the Berlin-based synth company, Koma Elektronik. Unlike traditional synthesizers that send audio directly to speakers, the Chromaplane creates electromagnetic fields that you interact with using special pickups, essentially electromagnetic microphones tapping into these invisible fields of sound floating just above the surface.
These pickups aren't new technology. Sound artists have been using them for years to uncover the hidden electromagnetic world all around us. Place one on your phone or laptop, and you'll get an idea of the ongoing digital chaos; but place it on the Chromaplane, and you'll discover a world of musical notes waiting to be explored.
How It Works
At its heart, the Chromaplane offers ten analog square wave oscillators. Each oscillator generates a note and emits it through an electromagnetic field made possible by a coil; the centre of this coil is visible as a small perforation on the surface. The aluminum surface acts as a physical filter, softening the harsh square waves into something more organic and musical.
What makes the Chromaplane special is that all ten oscillators are always speaking, making the instrument fully polyphonic. You decide which field to listen to by where and how you place the pickup. It's like tuning into different radio stations, but with your hands.
Playing Techniques
The beauty of the Chromaplane is in how intuitive and tactile it feels to play. You become the envelope, you shape the sound with your movements:
Position a pickup directly over a field to hear a single note
Mix multiple notes by placing the pickup between fields
Play harmonies using two pickups simultaneously
Sweep across the surface to draw melodies
Strum for arpeggiated notes in one motion
Create rich drones by connecting multiple pickups through a headphone splitter
Make pendulum effects by dangling the pickups above the surface
Want a slow attack and long release? Just slowly bring the pickup toward the surface and gently pull it away. Short attack with long decay? Quickly place the pickup down and slowly lift it. You create any envelope shape you want with your movements, no preset parameters needed.
In Detail: Polarity
The pickups are polarized, which opens up fascinating sonic possibilities. Flip a pickup over, and you will change the phase of what it hears. Place two pickups near each other, one flipped on its head, and you'll hear phase cancellation as the signals partially cancel each other out.
One of our favorite techniques is playing "double notes." When you place a pickup horizontally across a field, both poles interact equally, creating a filtered sweet spot. Move slightly left or right, and the note reappears. This lets you create interesting double-note patterns just by moving horizontally across the surface.
Alternative Pickups
While the Chromaplane comes with specific pickups, you can experiment with almost anything: guitar pickups, headphones used as electromagnetic microphones, or even DIY pickups. Making your own pickup is surprisingly simple, just wind enamel copper wire about 300 times around something to create a coil. The larger the loop area and the more windings, the more sensitive it becomes to electromagnetic fields.
Shaping Your Sound
The Filter
The Chromaplane includes a voltage-controlled lowpass filter that's perfect for sculpting its harmonically rich tones. You can:
Manually adjust it while playing
Modulate it with control voltage for dynamic effects
Create ring modulation-like effects by turning up the CV with nothing plugged in
Generate subharmonics when dialed in just right (my personal favorite sound)
Use the envelope follower so your distance from the surface changes the filter cutoff
Experiment with external LFOs or random voltages
Crank the resonance for self-oscillation, essentially turning it into a sine wave oscillator
The Delay
The built-in low-fi delay (based on the PT2399 chip) adds incredible depth to your sonic explorations:
Control dry/wet, time, and feedback via thumb wheels
Modulate time with CV for flanger-like effects
Use the envelope follower for subtle pitch modulation or wild experimental sounds
Create ducking effects thanks to the analog soft clipper
Finding Your Tuning
Tuning the Chromaplane is an important part of defining your sound world. Since all notes drone subtly in the background, their relationships matter. While you could use a traditional chromatic scale, I recommend starting with fifths, octaves, and other consonant intervals.
The instrument is currently shipped with a D minor-centered tuning, but you can adjust each oscillator using the precision screws. The row closest to you produces the lowest pitches, so it makes sense to place lower notes on the bottom row and higher ones at the top. Octave switches allow you to lower each row by an octave for even more flexibility.
There are three main ways to tune:
Tuning by ear: Play one note as a reference, and tune others based on the beating patterns between notes. This approach feels immediate and musical, considering the relationships between all the notes.
Using the electromagnetic tuner: It works like a regular guitar tuner! Place it over a note to see if it's flat, sharp, or in tune (referenced to A440).
Using our tuning website: Play reference tones through a speaker while tuning the Chromaplane to match, either by ear or using the tuner with the "display notes" function.
External Input and Feedback Madness
One of the fields includes an external audio input. While you'll always hear the oscillators droning in the background, you can mix in other signals, perhaps a sequence, another oscillator, or a field recording.
This input also enables fascinating feedback paths. By routing the output back to this input, you can:
Control filter resonance or delay feedback using just the pickup
Create different effects by flipping the pickup's polarity
Generate strange artifacts by adjusting the filter cutoff CV
Design pickup-controlled effect sends
Join the Exploration
The Chromaplane offers a unique approach to sound synthesis and performance that's at the same time intuitive but not discounted.
If you'd like to hear how we use the instrument in our own music, check out Passepartout Duo's recordings and performances. We'd love to hear what sounds you discover in the electromagnetic realm!
