In Depth

The WaveSwarm ia an all analogue module which emulates the sound of multiple oscillators in unison - so how does it do that? Well, if we listen to s single VCO producing a Sawtooth or Triangle wave it sounds quite flat and uninteresting, however if we adda a second VCO with exactly the same waveform and frequency we get a much fatter sound - but only if they are SLIGHTLY out of tune with one another - if they are EXACTLY the same frequency and in phase then they go back to soundling thinner, like a single VCO.

The secret is that when we have a very slight de-tuning of one VCO against the other we get "beating" between them due to heterodyning, the beat frequency is actually the difference in frequency between them. This beating effect generally sounds most satisfying when the beat frequency is between 0.1hz to 1.5Hz.

Because of this low frequency "beating" effect the two waveforms are moving in and out of phase with one another at the beat frequency, and producing more complex waveforms as a result, this is because the two waveforms are added and subtracted together in a constantly changing combination, which repeats at the beat frequency and as a result produces a much fatter and more interesting sound.

Now, if we add in a third VCO, and slightly detune it against the other two VCO's so that it is running at a different beat frequency, then we create an even more complex and interesting sound, a huge, classic three VCO unison sound.

This is exactly the effect that we can achieve with the new WaveSwarm module, and it offers two six stage wave animators, channel A and Channel B. If we look at Channel A in the Block Layout and Signal Flow diagram below it can be seen that we have six individual Wave Animators wired in parallel, and each wave animator is modulated by its own dedicated LFO, all of which are preset to individual, and different, fixed frequencies.

 

Block Layout Diagram

 

A larger pdf version of the WaveSwarm block layout can be found here

 

Overview

We can see that each of the two channels (A and B) comprise six wave animators which are connected in parallel. Each individual animator has its own dedicated, fixed frequency LFO.

The individual animators are fed into an audio mixer, so that each has its own level control which can be adjusted to set the levels of each of the six outputs within the overall output mix. The mixer has a seventh input, which allows us to mix the incoming Dry signal with the wave animations. The mixer is followed by a soft clip circuit, with a soft clip incication LED.

The A+B output is the sum of both Channel A and Channel B, and as Input A is normalised to Input B this arrangement allows all twelve animators to be used on a single input signal.

The individual frequencies of each of the LFO's are:

Channel A - 0.16Hz, 0.25Hz, 0.38Hz, 0.55Hz, 0.8Hz, 1.2Hz

Channel B - 0.14Hz, 0.2Hz, 0.3Hz, 0.45Hz, 0.65Hz, 1.0Hz

 

 

Getting the best from the WaveSwarm

When a sawtooth or triangle waveform is patched to the input of the WaveSwarm module it needs care in setting the individual animator levels to get the best from it - there is a knack in balancing everything up so that we get a nice balance sound from the output - particularly when using most or all of the animators together. The animators interact with each other, so the best approach is to start with Bank A - initially set all controls to zero and then set the Dry A level to around 50%. Now try adding one animator at 40 or 50% level, we should hear what sounds like the original VCO along with a second VCO that is slightly detuned against it. Now gradually add in a second animator until they all sit nicely together and it sounds like three VCO's beating together, then add in a third animator and so on, adjusting individual levels up or down as we go so that we do not get a single, overpowering repetitive beating - we are looking for a pleasing mix of all of the animators from the output. The WaveSwarm is very much an instrument and needs experience and careful setting up to get the best from it - the "everything set to 10" approach certainly doesn't give good results, to get the best from it all of the animators need to be carefully balanced against each other, however it is worth the effort in mastering it as each channel can create unbelievably rich sounds from a single VCO. Once we have Channel A balanced up then try adding a second VCO to Channel B, and detune this VCO by an Octave. Now monitor the the B Output, again balancing up all of the individual animator levels to create a pleasing sound. With both Channels set up in this fashion we can now take the output from the A+B jack and hear all 12 Animators along with the original VCO's.

The best animator sounds are usually obtained by patching a sawtooth, ramp or triangle waveform to the inputs. Obviously other waveforms can be used too, and we would encourage experimentation, but do note that the waveforms themselves should be bipolar (+/-10V p/p). Also, because of the way that the animators function you may find that square and pulse waveforms do not give useful results.

The overdrive LED indictates when the overall level from all of the animators (and the dry mix signal) go over a threshold level and cause soft distortion in the output stage. Unlike regular overdrive circuits this actually softens the overall sound as it rounds out and slew limits the transients. We encourage you to experiment with different levels on each of the animators and dry mix so that you can experience the difference between the regular and overdriven sounds.

The WaveSwarm is not designed or intended to be used without an input signal, it will produce a cracking or clicking noise from the output in this configuration as the animators are looking for a signal to latch to, and as there is no signal present they will just trigger off the noise floor and create a rather unpleasant crackling and clicking noise on the output. So always make sure that a suitable input waveform is patched into the input for best results.

Do note that the WaveSwarm is NOT a signal processor and that is not it's intended use; it is designed to create rich multiple VCO like waveforms from a single VCO rather than for treating music. Feeding music and patches with varying amplitude into Input A or Input B will not give good results, in quieter or silent passages it will produce the noise glitching mentioned above as the animators have nothing to latch to. A suitable VCO with a ramp, sawtooth or triangle waveform should always be connected directly to IN A or IN B, without any modules in between so that it receives a contant waveform of constant amplitude, and any signal processing should be done downstream of the WaveSwarm module itself. Therefore the output of the Waveswarm should be treated in exactly the same way as the output of a VCO or mix of VCO's (because it is emulating multiple VCO's) i.e. it is always producing sound at a constant level. Obviously as the pitch of the VCO waveform goes up and down the WaveSwarm will track this so that it sounds like multiple VCO's. So just to be clear, we always apply any filtering and VCA amplitude enveloping (along with any other signal processing) AFTER the output, never between the VCO and the Waveswarm input.

 

Online video user guide

Here's a new in depth tutorial and online user guide for the WaveSwarm from Wayne Taylor, showing how to get the best from your WaveSwarm module.

 

What does it do and how does it sound?

An excellent demo video / review from DivKid Ben that gives the WaveSwarm a thorough workout.

The original Divkid youtube video with timing Index can be found here

 

 

Lets get massive!

How about using twelve AJHSynth MiniMod VCO's feeding into 12 channels of WaveSwarm modules to create the massive sound of 84 VCO's! This incredible setup is being used here by award winning composer, producer and arranger Lester Barnes to re-create the famous THX Deep Note movie intro..

 

Designed by...

The all analogue WaveSwarm circuit was designed by our good friend Jorg, a creative genius who lives and works from a secret, hidden cave in the Grand Canyon in Arizona. This unmapped network of underground caves are rumoured to have been dug from solid rock centuries ago by a small group of Ancient Egyptians who fled the great Nile flood and crossed the Atlantic Ocean to settle in the US centuries before Columbus.

Jorg has many decades of analogue design experience and has been active since the early days of modular synthesisers. Now living completely off grid, he toils endlessly each day indulging in his two favourite persuits; creating new and exciting analogue synthesiser circuits and growing the world's longest beard. Jorg is so old school that despite being heavily involved in the formative years of Silicon Valley he now completely shuns computers and instead insists upon drawing schematics on hand made papyrus, using a thin reed brush dipped in ink. All of his design computations are done by hand, and when he runs out of digits he does his more complex calculations using his trusty old abacus and hieroglyphic look up tables.

Here at AJHSynth we take Jorg's ideas and with great diligence and pride turn them into living, breathing Eurorack synthesiser modules. Our dream is that one day we will be as analogue as Jorg himself....

 

 

 

 

 

 

 

 

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