5 Synth Techniques to try with Circle²

If you’re just getting started with Circle² try out some staple synth techniques with these quick and easy to follow video tutorials.


Chances are, you’ve heard these sounds before. If you’re new to Circle² these techniques are a good way to get familiar and be well on the way to creating your own unique sounds!


1. Vinyl Stop FX

In the analogue days, this is the sonic effect that would occur from slowing down and starting up a vinyl record or analogue tape. This effect is created by manually applying and releasing friction. Now let’s get into the digital approach.

Here’s how the Circle² Echo Effect Module can be used to create vinyl stopping style FX:

  1. Load up any basic bass patch
  2. Set a continuous arpeggio by selecting Hold and playing a sequence of notes on your keyboard
  3. Turn on an LFO and drag it’s modulation circle to the time parameter of an Echo effect module
  4. Turn the Echo mix slider up fully

Voilà – instant turntable scratching style FX!

For further refinement, experiment with the Echo Delay Time and LFO modulation rate settings.


2. Self-Oscillating Filter

Although analogue synths have been capable of self-oscillating since the 1960’s, the effect wasn’t fully harnessed for decades. To define self-oscillation simply, it is a form of electronic feedback. Over the years this effect has found many uses including analogue kick-drum sounds, earth-shaking sub-bass, and a range of special effects sounds. For a more in-depth breakdown check out the KVR Audio Forum on this topic.

When certain analog filters are used with extremely high resonance settings they begin to self-oscillate, becoming their own sound source. The Analog Modeled Filter in Circle² behaves in the same way.

  1. Set up a new patch with all oscillators switched off
  2. Turn on the Filter and push the Resonance to full
  3. Assign a randomized Sequencer to modulate the Filter Frequency
  4. Go ahead and layer with oscillators for an out of this world sound!

3. FM Synthesis

Frequency Modulation Synthesis was discovered by Stanford professor John Chowning in the 1960’s and is considered one of the greatest breakthroughs in digital sound synthesis. A sinusoidal carrier of frequency and a modulator of frequency are used to generate an entirely new frequency.  The carrier frequency most resembles the fundamental frequency, while the modulating frequency alters the carrier frequency to create overtones and harmonic partials. Use this effect for enhanced tonal texture and complex sounds. Check out this quick video for a visualization or this article if you really want to get into the nitty gritty.

All Circle² oscillators can also be used as modulators. That is, extremely fast LFOs.

  1. Turn on 2 Analog sin oscillators
  2. Drag the second oscillator modulation circle to control the Coarse tuning of the first
  3. Next we set the Coarse tuning of the second oscillator to 24, and set its Level to 0
  4. Now experiment with different oscillator shapes and tuning settings

4. AM Synthesis

Like FM synthesis, Amplitude Modulation Synthesis utilizes two oscillators as carrier and modifier frequencies. Instead of altering frequency, the modifier alters the amplitude. When the modifier is running slowly, as with an LFO, you’ll hear the volume increase and decrease. When the modifier is running faster it creates unusual harmonics.

All Circle² oscillators can also be used for AM synthesis, where one or more is used to modulate the output level.

  1. Turn on 2 Analog sin oscillators
  2. Drag the second oscillator modulation circle to modulate the Output Level
  3. Again, experiment with tuning levels and wave shapes – AM can have some really crazy results!

5. Synthesizing Drums

With an instrument such as the violin, sound is created from a string that is stretched and depressed with the fingers to create tension along one dimension – its length. This creates partials that are harmonically related. A drum, however, also creates partials that are not harmonically related. The vibrations travel in a more complex way through the surface of a drum which creates dense clusters of unrelated harmonic frequencies. To create synthesized drums you’ll utilize different techniques and layers that mimic dense clusters of unrelated harmonic frequencies.  Head over here if you want to take a deeper dive.

Let’s start with synthesizing a kick:

  1. Use a sharp decaying envelope to control the pitch of an Analog sin wave oscillator, and the Frequency of the Noise Oscillator.

Next we’ll synthesize a shaker loop using filtered white noise:

  1. Turn on both the noise oscillator and the Arpeggiator (in sync mode at a 1/4 rate)
  2. Raising the frequency, we turn on a bandpass filter
  3. Assign a sequencer to modulate the filter frequency for added rhythm