Make a sound compatible with itself (Patreon)

In this video, I explored how overtones and their rhythmic structure play a crucial role in making sounds cohesive, especially when you're trying to play chords. If you've ever sampled a sound or created one, then tried to play multiple notes or chords and found that it sounds terrible—this is why! The rhythm and order of the overtones dictate whether a sound feels like a single entity or a messy clash of notes.

I also demonstrated how Comb Filters in Bitwig Studio can be used to "order" overtones and make a sound playable as chords while still sounding harmonious. This approach works especially well for turning complex, messy sounds into lush, playable instruments.

Why Overtones Matter:

Single Sound vs. Chord:

When overtones (harmonics) follow a strict mathematical order (e.g., multiples of the fundamental frequency), the brain interprets the sound as a single, cohesive entity.

When this order is disrupted, the brain hears separate notes or a "chord," even if you didn’t intend that.

This is why playing chords with improperly tuned overtones sounds unpleasant.

How Overtones Lose Order:

Voice stacking or detuning creates overtones that no longer align mathematically.

Playing multiple notes amplifies this issue, making the sound dissonant.

How to Fix This:

I demonstrated several ways to reorder overtones and make sounds playable as chords:

Using Bandpass Filters:

Isolate the fundamental frequency with a bandpass filter using key tracking.

Boost the resonance to emphasize the fundamental and suppress other harmonics.

Works well but only targets one frequency at a time, so it's limited.

Using Comb Filters:

Comb Filters naturally amplify the harmonic series of the input sound.

When tuned to the fundamental, they bring order to the overtones.

Multiple Comb Filters can amplify specific harmonics while suppressing the in-between frequencies.

This creates a "harmonically aligned" sound, making it suitable for chords and progressions.

Practical Examples:

Simple Sine Wave and Comb Filters:

I created a basic sound using sine wave oscillators and routed it through Comb Filters.

With the Comb Filters, the sound became more cohesive and playable across multiple notes.

Without the Comb Filters, it sounded messy and dissonant.

Using Noise as a Sound Source:

I loaded noise into a sampler and played it raw—it sounded chaotic.

By routing the noise through a Comb Filter with key tracking, it transformed into a playable instrument.

The Comb Filter emphasized the harmonic overtones, creating a smooth sound that works for chords.

Layering with Sampler and FX Grid:

I used a sampler with a noise sample and inserted an FX Grid containing a Comb Filter.

This allowed the Comb Filter to track pitches properly and amplify the harmonics, creating a lush, playable sound.

The result: a beautiful pad or lead instrument.

Why Comb Filters Work Better:

Unlike a bandpass filter that isolates a single frequency, Comb Filters amplify all harmonic overtones in the harmonic series.

This brings order to the sound, aligning overtones mathematically and making it playable across multiple notes.

With resonance adjustments, you can control how prominent the harmonics are, making the sound either subtle or exaggerated.

Creative Applications:

Use Comb Filters to create pads or leads from chaotic sounds like noise or FM synthesis.

Add reverb (e.g., Valhalla) for lush, expansive textures.

Modulate parameters like pitch or resonance over time to create evolving, dynamic sounds.

Record the processed sound and resample it for even more control.

Key Takeaways:

The rhythm of overtones determines whether a sound feels cohesive or dissonant.

Comb Filters are a powerful tool for aligning and amplifying overtones, making sounds more usable for chords.

With the right setup, even noise or chaotic FM sounds can be transformed into playable instruments.