Make a sound compatible with itself

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.