Reaktor Secrets Revealed!
Pages: 1, 2, 3, 4

Golden Waves of GrainStates SP

The Ensembles in the Classics folder aren't documented in the Instrument Guide, which is a shame, because there are some great musical instruments among the Classics. One of my favorites is the granular synthesis step sequencer called GrainStates SP (see Figure 10). This instrument baffled me when I first fired it up. The way to learn it, I found, was to simplify the patch and work with one control at a time.

Figure 10: GrainStates SP Figure 10. GrainStates SP deconstructs a sample into short grains. The eight modules each provide separate settings for grain playback. You can step-sequence the modules or trigger them live using a MIDI keyboard. (Click to enlarge.)

GrainStates uses a single waveform as source material; this is selected using the Sel knob in the lower left corner. You can also load your own wave. Spoken word phrases can be great fun, as you can hear in this before-and-after demonstration:

The eight identical modules in the center area are the sequencer steps. Each step has a set of controls for the playback of audio grains. But the labels on the controls are cryptic, and the information in the tooltips is incomplete. Here's how to start learning the instrument:

  1. In the Sequencer Control section (lower left) click the Man (manual) button to light it. That shuts off the sequencer, leaving only one of the steps active — the one with the red light. In manual mode, you choose a step using the SelS knob. Note that this knob lets you set a position between two of the steps. For learning purposes, set it to a whole number so you'll only hear the output of one step.
  2. Turn the D/W (dry/wet) knob in the lower right corner all the way to the left. That will shut off the delay effect, making it easier to hear your experiments.
  3. In the Globals area, turn PnJ (stereo pan jitter) all the way to the left.
  4. Set the PJ (pitch jitter) slider for your active step all the way to the left.
  5. Set PS (pitch slope) and TP (transpose) to zero.
  6. Turn the Smr (smear) knob all the way to the left, and set a suitable volume level with the vertical slider. At this point you'll be hearing a single grain (a short segment) of the waveform, which will loop endlessly in a boring way.

Begin your experiments by dragging the crosshairs around in the square control area. The X coordinate controls the position of the grain (you'll see a vertical line move in the waveform display), and the Y coordinate controls the length of the grain. Extremely short grains will produce a sustained tone.

Turning up the Smear knob will cause grains of varying lengths to overlap. Moving the PJ slider to the right will give each grain a different random pitch. The Glp and Glv knobs don't do anything, because they control the transition from the previous sequencer step to this one. In order to hear the transitions, you'll need to start the sequencer.

For the sequencer to run, the Reaktor start button in the panel toolbar has to be pressed. In addition, you have to make sure that the mSel (MIDI select) button in the MIDI section is not lighted, as this button overrides the sequencer. The button allows steps to be triggered manually from a MIDI keyboard.

In the sequencer control section, set NrSt (number of steps) to two. That will cause only the first two steps to be active. Set the controls for these steps to different values and listen to the changes in sound color. The Glp (pitch glide) knob will work only if the two steps have different transpose values; the Glv knob interpolates between the other settings during the transition to the new step.

GrainStates has a number of other features, but this quick guided tour should give you a better idea what you can do with it.

May I Have a Banana with That?

Even if you're not ready to dive into designing your own synthesizer in Reaktor, there are some simple things you can do to expand your sound palette. Adding an effect processor to an instrument is a good place to start. Many of the factory Ensembles contain only one instrument. You can view this by right-clicking on an empty part of the panel window and selecting Ensemble Structure from the pop-up menu (see Figure 11).

Figure 11: Ensemble Structure Figure 11. The top-level structure of most Reaktor Ensembles is quite simple: a single instrument sends its signal to the Audio Out object.

Right-click on a blank spot in the Ensemble Structure window and select Insert Instrument > Effects. The Banaan Electrique multi-effect might be a good choice. (Yes, that's Dutch for "electric banana," a reference to an ancient song by Donovan.) After inserting the effect, delete the wires connecting the synth to the Audio Out module, reconnect them to the effect's inputs, and connect its outputs to the Audio Out (see Figure 12).

Figure 12: Adding an Effect Figure 12. Here, I've added an effect to the Ensemble, patching it between the instrument and the output.

Okay, Just One More Tip . . .

With much of Reaktor's factory library, switching from the A panel to the B panel does nothing: the two panels are identical. After trying this a few times, you may give up and assume that what you see is what you get. That would be a mistake.

The Kaleidon synth, found in the Classics folder, arrives from the factory with the B panel active. Unlike many Reaktor synths, Kaleidon doesn't have identical A and B panel views. Click on the A panel and drag the corner of the window down until you can view the whole thing (see Figure 13). This is where most of the parameters of this massive synth are hiding.

Figure 13: Kaleidon Figure 13. More knobs and switches than any three synthesists could ever need are available in the A panel for Kaleidon, one of the Ensembles in the Classics folder. (Click to enlarge.)

Get Radioactive

A nuclear reactor is a hot place that produces new, unstable isotopes. That's a pretty good description of Reaktor, too. In this article I've had room to explore only a tiny subset of the program's capabilities. Now it's your turn, so don that protective gear, grab the fuel rods, and watch your computer start to glow.

Jim Aikin writes about music technology for a variety of publications and websites. His most recent books are Power Tools for Synthesizer Programming and Chords & Harmony.

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