Natural Synthesis

OrchestraOne objective that is common to perhaps every patch I design is to create a minimally electronic-sounding  character.  Failure consists of making a synthesizer scream, “I’m a synthesizer!”  Rather, my goal is to make the synthesizer sound similar to acoustic instruments, such as strings, brass, and reeds, or even better, lungs and throats.  I strive to achieve a heaving breathing effect, so that the synthesizer has a living and organically dynamic personality, much like an orchestra or a choir.  This effect obviously wouldn’t suit organ, harpsichord, chime, or piano patches, but it’s something I consistently strive for, even when a particular patch has no relation to a traditional instrument or ensemble.

First, there’s one challenge.  Because most often both my hands and feet are occupied playing keyboards and the pedalboard all at once, I don’t have the luxury of easily manipulating parameters to achieve the effect.  The one exception is in awkwardly stretching a finger of my left hand to move the modulation wheel, which is often programmed to open the filter cut off frequency.  This allows me to make dynamic changes, but only with some difficulty, since the other fingers of the left hand are probably busy playing a musical line or sustaining chords.

The solution to achieving a natural heaving breathing quality comes through two-fold modulation.  In designing, for example, a string patch or even an icy digital pad with a living character, I will add just a touch of filter modulation to the envelope.  The attack phase will slightly and slowly open the filter, and then slowly close it with the decay all the way down to the sustain level.  That method is common enough, but more importantly, I use an LFO as well.  The heaving effect comes by setting an LFO to very slowly open and close the filter a moderate amount.  On the Poly Evolver Keyboard and Prophet ’08, this means setting the LFO rate to 8-12 and the amount/depth to 10-20, depending on the needs of the piece of music.  The LFO also has to be set to retrigger all the voices with each key strike using the “Key Sync” button.  Thus, when you sustain a chord for several seconds, the voices will “heave,” giving a living breathing effect.  This constant but gentle swelling of the filter gives a piece of music a beautifully subtle modulating dynamic that can be controlled by playing technique.  If you want the swell, then simply sustain a note or chord; if you don’t want it, then keep retriggering the note or chord.  This will prevent the filter from having enough time to open.

What is so useful about this method is that it allows you to have dynamic changes throughout a piece of music, even when your hands and feet are constantly engaged and, therefore, unable to manipulate a wheel, parameter, or pedal.  So, it’s essential for the one-man-ensemble arrangement.

I use this sound design method in nearly every polyphonic patch, and many of the monophonic ones as well.  The fact is, acoustic instruments and the human voice are not static sound sources; they have natural fluctuations, and also interact with other acoustic influences.  My objective with this technique is to imitate this complexity in order to eliminate, as best I can, the inherently sterile electronic qualities of the synthesizer.

Improvisation #83 for Poly Evolver Keyboard and Prophet ’08

A slow and dreamy synthesizer piece.

This improvisation makes use of a soft metallic digital pad on the Poly Evolver, a string pad on one Prophet ’08, and a flute-like solo patch on another Prophet ’08.

The digital pad is either mellow or shrill, depending on the setting of the filter cut off frequency, which is controlled by the modulation wheel. Its extreme upper range has much digital aliasing.

The Prophet ’08 string pad uses a 2-pole filter setting with a high resonance level,, and its filter is similarly controlled by the modulation wheel. As always, the filter is very slowly modulated by an LFO. This creates a slight crescendo whenever a note or chord is sustained and gives the pad a slight heaving/breathing quality.

The flute sound seems simple but is deceptively elaborate. It consists of a narrow pulse and a square. The pulse width of each waveform is very slightly and slowly modulated. In addition, an LFO slowly modulates between one oscillator and the other. This means there is a subtle chorus effect from the PWM, a changing of timbre as the narrow pulse changes to a square and then back again, a faint beating of oscillators when the two briefly meet in the middle, plus a delayed vibrato which can be either maintained by a smooth connected playing technique or retriggered (and thus, delayed) by a disconnected playing technique. Its filter, too, is controlled by the modulation wheel. To deepen the richness of the patch’s general tone, the identical sound of Layer A is copied to Layer B and the two are panned at the mixer. So much trouble for a simple little flute sound, but it’s always worth it. Of course, all these effects are detectible only when a long note is heard, and that’s fine, because they’re meant to be musical nuances that don’t overly attract attention to themselves.


DSI Prophet ’08 Keyboard (2)
DSI Prophet ’08 Module
DSI Poly Evolver Keyboard
DSI Poly Evolver Rack

DSI Evolver Desktop
Hammond XPK 200L Pedalboard

Lexicon MX300 for reverb
Alesis Nanoverb 2 for delay

Performed live and recorded directly to a Tascam CD-RW900 Mk II.