Arturia Pigments: Building Evolving Pads (With Modal Synthesis)

Marula Music
Nov 12
5 min read

Modal synthesis is one of those sections in a synth like Pigments that many producers gloss over. It's not as immediate as an analog-style oscillator, and "modal" sounds more like music theory than sound design.

It can however be pretty powerful for creating some otherworldly textures, bells, and granular-style pads. The problem is that it’s often misunderstood.

Let's deconstruct it.

The Core Concept: Exciter + Resonator

The Modal engine in Pigments is not a typical oscillator. It doesn't generate a continuous waveform on its own. Instead, it's a form of physical modeling that works in two parts:

The Exciter: This is the sound source. Think of it as the "action"—a plectrum hitting a string, a mallet striking a metal bar, or friction from a bow.
The Resonator: This is the body of the instrument. It’s essentially a bank of resonant filters that are "excited" by the sound source. The material, shape, and properties of this resonator are what define the final timbre.

In Pigments, you have two primary exciter types you can blend:

Collision: This is a transient. It's an impact, like a strum or a strike. You can use modeled noise, a one-shot sample, or even sidechain an external audio input (like a drum loop) to "strike" the resonators.
Friction: This is a sustained or continuous exciter. It’s a noise or impulse source that is constantly re-triggering, creating a sound more like bowing, scraping, or even a granular-style texture.

For this patch, we're going to use the Friction exciter. It’s excellent for creating evolving pad sounds because it provides a consistent signal, which we can then shape.

Deconstructing the Patch: An "Otherworldly" Pad

Our goal is to build an evolving, textural, "otherworldly" pad.

1. Engine 1: The Modal Texture

This engine will be our main texture.

Engine Type: Select the Modal engine.
Exciter: We'll use only the Friction exciter. By default, it sounds a bit like a saw wave (strings and saw waves are harmonically similar), but we're going to change that.
Friction Density: This control is key. It sets how many "particles" or impulses are in the friction noise. Turn the Density down, and you can hear the individual impulses—it sounds almost granular. We'll set this as our first point of modulation.

Modulation 1: Organic Variation We want this texture to feel alive and non-static.

Go to the Rand tab and select a Voice Modulator. This modulator generates a different random value for every new note (polyphonic randomness).
Assign this Voice Modulator to the Friction > Density control with a subtle amount.
Why this works: Every key press will now have a slightly different granular density, adding immediate variation and preventing the patch from sounding sterile.

2. Shaping the Resonator

Now we move to the "Modal" section, which controls the resonator itself.

Profile: You have two options, "Strings" and "Beam." We'll stick with Strings for now, but "Beam" is great for more metallic, bell-like tones.
Warp: This is a powerful control. It fundamentally re-pitches the harmonics (the resonant peaks) of the resonator. Warping it up thins out the sound and pushes the harmonics higher.
Range: This is critical. It locks the first 'X' harmonics in place, protecting your fundamental frequencies from being warped. We'll set this to 1 or 2 to keep the root note stable while the upper harmonics move.

Modulation 2: Slow Phasing To get a slow, evolving, phasy character, we'll modulate the Warp control.

Assign LFO 1 to the Modal > Warp parameter.
Set the LFO 1 Rate to be very slow (e.g., 0.100 Hz).
Why this works: This LFO is now slowly shifting the harmonic content of our sound, creating a constant, subtle timbral movement.

Modulation 3: Polyphonic Desynchronization Right now, every note we play will have its LFO moving in lock-step, which can create an obvious "flanging" sound. We want each note to evolve on its own.

Assign the same Voice Modulator from before to the LFO 1 Rate. Use a very small amount.
Why this works: This is a classic polyphonic modulation technique. Each new note will have its LFO running at a slightly different speed, desynchronizing the modulation and making the whole pad feel wider and more organic.

Finally, in the Modal > Shape section, increase the Length slightly. This blurs the individual particles together, making the sound more of a continuous, ringing string and less of a discrete granular cloud.

3. Engine 2: The Harmonic Foundation

Our modal texture is great, but it lacks a solid foundation. We'll use Engine 2 for a clean sub-bass.

Engine Type: Select the Harmonic engine.
Technique: We only want the low fundamentals. The "Partials" control determines how many harmonics are active. By turning the Partials knob down, you are reducing the harmonic resolution, which acts as a very steep low-pass filter.
Modulation: Assign Env 2 (with a simple plucky shape) to the Partials control. This will give the sub-bass a gentle attack.

4. Advanced Voicing: Keyboard Tracking

We want the bass sound for the pad to be prominent in the low octaves and the texture engine to float on top, without them fighting for space.

We use Keyboard Tracking (the "Key" assignment) to control parameters based on what note is played.

Engine 2 (Harmonic): We want this to be quieter as we play higher up the keyboard.
- Assign Keyboard tracking to the Engine 2 > Level.
- Set the amount to be negative (e.g., -1.00). Now, the higher the note, the lower the volume of our sub.
Engine 1 (Modal): We want this to be quieter in the low-end, so it doesn't muddy the sub.
- Assign Keyboard tracking to the Engine 1 > Level.
- Set the amount to be positive (e.g., +0.50). Now, the lower the note, the quieter our texture is.

Why this works: We've effectively created a frequency "crossover" using keyboard tracking. The bass engine dominates the low octaves, and the modal texture dominates the mid and high octaves. This is far more precise than just EQing the final patch.

5. Filtering and Effects

The patch is built, but now we need to place it in a space.

Filters: We'll use a serial filter setup to add more resonant character.
- Filter 1: Set to a Comb filter. This will add more of that ringing, metallic quality we've been building.
- Filter 2: Set to a standard Low Pass filter (like the SEM) to tame the high-end.
- Routing: Make sure the Filter Routing is set to serial (Filter 1 -> Filter 2) and blend the Comb filter's output partially.
Effects (The "Wash"): Our goal is a washed-out ambient sound.
- FX A: Shimmer Reverb. This is the core of the ambient sound.
- Important: We will use this as an Insert effect, not a Send.
- Why this works: Using a reverb as an insert (with a high Wet mix) intentionally washes out the dry signal completely. We aren't trying to put our "dry" sound into a room; we are trying to drown the sound and blend it into one cohesive, blurred texture.
- FX B: Add a Pitch-Shifting Delay to add more octave harmonics.
- FX C: Use a Compressor at the end of the chain, acting as a simple leveler to control the dynamics.

The Result

By starting with a clear ]understanding of the signal path (Exciter -> Resonator), we've built a patch that is complex, organic, and evolving. Modal synthesis isn't just for bells; it's a deep textural tool.

You can grab the patch here to try out for yourself.