Granular synthesis may be one of the most interesting and, confoundingly, more difficult processes to achieve predictable results. But therein lies its charm… and its frustrations. Early software attempts at granulation (See the sidebar: “What is Granular Synthesis?”) were slow, and results were largely a product of trial and error. The resulting audio files weren’t playable unless they were loaded into a sampler or other playback medium. Often, the results were repetitive, static, or generally favored avant-garde, aleatoric productions. The adoption of granular techniques into software synthesis seem to have cleared the way toward more widespread acceptance.
Audio Damage Quanta forges granular with basic analog-modeled, subtractive synthesis and waveshaping to produce sounds useful to composers from the mainstream to the surrealistic and avant-garde end of the musical spectrum. Quanta provides 64-bit AU, VST2, VST3 and AAX plugins for Mac OS, with 32- and 64-bit VST2 and VST3, and 64-bit AAX plugins for Windows. There is no standalone version, so you will need a host application. You can also purchase an iOS version with Inter-App Audio.
A GRAIN OF DIFFERENCE
Quanta is rather austere and business-like in appearance; there are no realistic knobs and sliders, and no attempt to render virtual side panels with the look of real wood, jiggling patch cords, or painstakingly detailed knurled knobs; instead, and probably the first feature my ageing eyes appreciate, is Quanta’s simple, continuously resizable GUI. Drag the lower-right corner of the instrument to adjust Quanta’s display from screen-filling to eagle-eye-small, and all points in between (See Fig.1).
As a measure of user-friendliness, I like puttering around with as little reference to the manual as possible. Suffice it to say that if you understand basics of synthesis, the workflow shouldn’t be hard to grasp. The oscillator section occupies the bottom half of every page for easy tweaking (More about this shortly). The top left offers access to four main pages: Sample, FEG, FLFO, and Matrix. An elongated window at the top center opens the preset browser with a click at the left. Click on its right-hand side to open the instrument’s settings panel. The browser displays its banks of presets grouped by function or designer, with each bank’s presets tucked away into triangular disclosure buttons. Annoyingly, leaving the browser page resets it to its default state, with all banks unopened. A set of increment/decrement buttons would be welcome to explore banks without losing your place. On the positive side, a click anywhere in the window toggles the last of the four pages you were accessing. I found that toggling between the sample page and the browser was particularly handy when I wanted to drop my own samples from my desktop to audition them in different presets. You can load samples from a drop-down menu on the sample page, but dragging them from the finder is much quicker than navigating folders. A single click on a preset in the browser loads the patch and displays the sample file name as well as its sample rate and bit depth (See Fig.2). I was delighted to find that Quanta can be configured to support MIDI Polyphonic Expression (MPE), meaning that it can respond to Aftertouch, Pitch Bend, and the position of each note, independently. I spent the rest of the review shuttling between my Roli Seaboard 49 and my MIDI guitar; Quanta performed without a hitch.
SAMPLING THE WARES
Pulling a sample into Quanta couldn’t be easier. Quanta can handle stereo files in AIFF, FLAC, MP3, Ogg, and WAV formats at any rate and depth; however, it’s not a sampler, and doesn’t support multisampling. Once the sample is loaded, the large rectangular window presents a rounded-off, stylized overview of the waveform (See Fig.3). If the patch already contains modulation assignments, an animated blue dot will sweep back and forth for each voice played, in addition to a blue vertical line that indicates the starting position of the oscillator Granulator (more later).
The letter F appended to the EGs and LFOs stands for flexible. You can click and drag as many envelope segments as you need (See Fig. 4). You get four envelopes to play with, and you can set their playback modes to one-shot, forward, or backward looping. Dragging on an envelope segment creates a curve between stages. For patches with a rhythmic component, you can sync envelope points to your host program’s clock.
There’s no freehand design for the two FLFOs, but controls for Frequency, Phase, Shape, Skew, and Warp can produce plenty of LFO shapes ranging from the conventional to the downright weird (See Fig. 5). You can feed your LFO creations to an additional sample-and-hold LFO. All FLFOs supply knobs for frequency/rhythmic value, with an additional smoothing control for Sample-and-Hold.
The Matrix page offers 36 destinations and 14 sources, with sources arranged horizontally at the top, and destinations arrayed vertically on the left side of the grid. The 14 sources divide equally into internally-generated modulation sources and MIDI Control Change messages. Clicking and dragging in the grid will set up positive or negative modulation, depending on the direction of the mouse. It’s a fairly straightforward system, and of course, you can automate almost any parameter, but there is no MIDI Learn capability.
Inarguably, Quanta’s centerpiece is its Granulator section (See Fig.6). You get one analog-modeled oscillator, with continuously variable shape between sine and sawtooth wave, a pulse width/symmetry knob (depending on the oscillator shape), fine and coarse tuning knobs and oscillator level. To the oscillator’s right is a noise generator with level and color controls. You can feed either or both oscillators into the granulation section and produce some pretty fat, animated tones without even resorting to the sample oscillator.
As implemented in Quanta, Granular Synthesis is the OCD cousin of Wavetable synthesis, and Quanta’s Grains section will bear me out. The top row of knobs controls the number of grains and their length, each with a knob to dial in a degree of randomness for each voice. At the very center, a Shape knob sets an Attack/Release envelope to smooth or cause abrupt transitions between grains. With the Length knob, the size of the grains is variable between 1 millisecond and a full second. The manual omits the parameters of the Grain Tune knob, but you can tune the grains plus or minus two octaves, incremented in cents. Adding a subtle amount of randomization here thickens the sound up considerably. You can set playback direction, set a playback starting position, randomize it, set the stereo width, and more. The analog and noise oscillators are not simply grafted onto the granulated sample; Osc In and Noise In knobs subject the modeled tones to granulation along with the sample section. There’s plenty more, including a pair of configurable filters with a graphic interface that you can click and drag to shape frequency and resonance, but what does Quanta actually sound like?
Forget about realistic orchestral tones or accurate renditions of vintage synths; a casual stroll through Quanta’s presets will reveal a range of textures, from deliberately distorted and assaultive to atonal bell sounds that unpredictably shift timbre and tuning; delicate, glitchy pads, and tonal, synthy comps with subtle animation. Because you can import your own samples, the possibilities are limitless. As I often do, I raided my Native Instruments Absynth and Apple Loops sample libraries and produced some eminently useful and intriguing sounds. There's always an element of surprise, as the outcome of the granular process is hard to predict. I highly recommend Audio Damage Quanta as a synth for the creative and adventurous Electronic Musician.
Continuously resizable GUI. Drag and Drop samples. Granulator independently processes and merges samples with synth and noise sources. Wildly flexible envelopes and LFOs. MPE support
No MIDI Learn feature. No reverb or effects section. Browser resets after jumping to another page
$99 (download only)
What is Granular Synthesis?
We experience and depict sound as a continuous flow of changes in amplitude (loudness) and frequency (pitch and timbre) over time. Since the early stages of tape recording through current digital sampling technologies, we have been able to dissect, disrupt, and re-order that flow, with intriguing results. At the current state of sampling, linear playback of audio content and looping forward, backward, or alternating portions of the recording are commonplace. Advances in digital signal processing power and Random-Access Memory (RAM) led to quick and easy playback at any point and in any order on the timeline. Iannis Xenakis was probably the first to find musical purpose in the reordering of minute slices of sound by cutting and splicing prerecorded tape.
The theory behind Granular Synthesis is that a complex sound can comprise minute particles of sound, or grains. Changing the order, the duration, or the playback speed of the grains can create new sounds that bear little outward resemblance to the original content. Typically, the shorter the grain, the more detectable is the overall pitch. Taken individually, the grains are too minute for us to audibly or graphically identify it as a component of the original sound any more than we could identify a sine-wave component of a sound reproduced by additive synthesis as part of a whole. Once we line up the grains, end-to-end in a linear fashion, the sound would take on identifiable characteristics. However, if we were to take a sample then reorder and compile the grains, we would hear disruptions and discontinuities in the resulting sound — not unlike the bumps and clicks you might hear in a poorly-looped sample. Fortunately, envelopes applied to each grain can smooth out any jagged mismatches in amplitude, and the sheer rapidity of thousands of grains of sound can also help to level out the differences; think of a number of still frames in a motion picture. You can then animate the reassembled tones by sweeping them in random order. The processing power to carry out such tasks is immense, and the first computer-based granulating software were decidedly non-real-time applications, processing a signal or creating a waveform, granulating it, and then rendering a processed file.
With the powerful CPUs of modern computers, Granular Synthesis has evolved, from a number of digital-signal-processing applications to full-blown real-time granular synthesizer hybrids that meld granular and more conventional synthesis types. In fact, the process of time-compression and expansion features baked into your DAW rely on some principals of Granular Synthesis; In order to stretch and warp digital audio, the file is broken down into grains. A few good examples of Granular Synthesis audio processors are Ableton Live’s Granular Delay and Robert Henke’s Granulator II. Native Instruments Absynth, Propellerhead Reason’s Grain Sample Manipulator, Spectrasonics Omnisphere, Steinberg Padshop, and UVI Falcon — as well as Audio Damage Quanta — use real-time Granular Synthesis in conjunction with subtractive synthesis and other techniques to produce animated sounds that are unobtainable with conventional samplers and synthesizers.
Marty Cutler is the author of The New Electronic Guitarist, published by Hal Leonard