A quick overview of principles and aesthetics audio “resonance” in filters and beyond.
In synthesis, we often encounter resonance controls on our filters, both digital and analog, but, more broadly speaking audio resonance the property of any device, space, or system to increase the amplitude of particular frequencies.
So what? Well, that’s a good question. Here I offer some different examples of resonance, both acoustic and electroacoustic, and perhaps there are some avenues there for you to explore in your own music and sonic art.
0:00 Defining “Resonance” 0:50 I Am Sitting in a Room 1:11 Breaking a Wine Glass 1:39 “That Really Resonated with Me” 1:56 Resonant Bodies of Instruments 2:11 Feedback Loops 2:36 Resonance as Metaphor 3:09 Where’s the Art?
Building a resonant EQ in Reaktor Primary, taking inspiration from the Serge Resonant EQ’s unevenly-spaced frequencies and nonlinear controls.
In my regular journeys across the internet, I came across the Random*Source Serge Resonant EQ, a reissue of the resonant EQ from the Serge Synthesizer, and became a bit taken with its implementation and ideas. $400 is a bit too much for an impulse buy, so let’s see what we can do in Reaktor.
Even if we don’t end up with something that sounds perfect, we can use this as an opportunity to think more about subtractive synthesis, and talk about “parametric support” in our control schemes.
0:00 Purchase Your Way to Music Proficiency! 0:43 Random*Source Serge Resonant EQ 1:14 What’s interesting about this? 2:59 Disclaimer 3:22 Reaktor Primary Peak EQ 5:00 “Boost” vs. “Resonance” 5:53 Making Selectable Sound Sources 8:18 Throwing in an Oscilloscope 8:49 Starting the Resonant EQ Macro 9:28 Creating a Single Band 11:24 Level Controls to Avoid Clipping 13:13 One Knob for Resonance and Boost 14:28 “Funny Math” 21:13 Recapping the Flow / Fine Tuning 22:49 Duplicate! (for each frequency) 23:23 Setting the Frequencies 25:09 Adding a ByPass Switch 25:53 Sound Test 27:14 Saturator 28:04 Waveform Variance Across Instrument Range 29:38 Feedback 35:30 Next Steps
You can find a lot of lists out there on “Synthesis Techniques You Must Know!” These can be pretty compelling, but it can be helpful to take a broader look, and simplify synthesis into 5 big categories:
-Playback and Manipulation of Recorded Audio (Sampling and WT Synthesis) -Additive Synthesis -Subtractive Synthesis -Distortion Synthesis and Modulation Synthesis, and -Physical-Modeling Synthesis
By zooming out and thinking about these larger ideas, we make synthesis more accessible to people who are starting out, and we give a framework for people who are innovating new synthesis techniques.
0:00 Synthesis isn’t that complicated. 1:03 Five Categories for Synthesis Techniques 1:33 Playback and Manipulation of Recorded Audio 2:34 Additive Synthesis 2:52 Subtractive Synthesis 3:20 Distortion Synthesis (Modulation Synthesis) 4:08 Physical Modeling Synthesis 4:25 So What? / Hybrid Synthesis
Since sine waves are made up of only a single frequency, it’s not usually particularly effective to filter them.
Several of my students sent me Reaktor ensembles with filtered sine waves, so I wanted to quickly talk through why they’re not really the most effective thing to filter. I go through things in Native Instruments Reaktor, but the concept is applicable in whatever synthesis environment you’re working in–Pd, Max/MSP, Kyma, etc.