Sound Design Workshop: Steam Powered

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FIG. 1: Use Omnisphere''s Granular sample processor to add motion and harmonic interest to vocal presets.

With Spectrasonics Omnisphere's extensive library of Multis and patches, it's easy to get complacent and ignore the powerful Steam engine under the hood. In addition to clever takes on frequency and ring modulation, waveshaping, and voice multiplication, you get a host of modulators and a robust modulation matrix. Here are a couple of examples of how to add some steam to your patches.

Voices Adrift

Start with a new instance of Omnisphere or clear the Multi in an existing instance. That leaves you with the default patch, in which only Layer A is active. Select the Edit tab, display Layer A, select Sample mode, and load the sample Boys Choir Ah-Eh-Ee-Oo from the Human Voices category in the Sample Browser. Play a sustained note, and you'll hear the boys choir cycle through the four phonemes indicated in the name.

Activate granular synthesis under Layer A's Mult tab to add some motion and harmonic interest. With the Grain Depth slider at its default (full left), you'll hear a series of grains of varying lengths. Increase the slider, and you'll get more grains, which overlap and fill the gaps. Higher values take more CPU, and settings in the first third of the slider's range usually work well. Also increase the Intensity slider to vary the grain spacing.

Increase the Pitch Grains slider, and some of the grains will jump in pitch by the amount set with the Interval slider (12 semitones by default). The choice of interval depends on context, but five semitones is a fairly neutral choice that avoids wide jumps. The buttons in the middle of the two columns of sliders set the shift direction, and the bottom button gives the most variety, allowing random shifts in both directions. Use the Gliding and Smoothing sliders to smooth pitch and volume transitions. Use the Spread slider to distribute grains across the stereo field (see Fig. 1).

A quick way to expand on this patch is to copy Layer A to Layer B and then choose a different vocal sample. For easy auditioning, right-click on the Mix A slider and select MIDI CC Learn. Next, assign it to a convenient controller, and assign the same controller to Mix B using MIDI CC Learn Inverted. You can then change samples for Layer B in the browser while adjusting the mix.

Once your Layers are set up, try transposing one by a fourth, a fifth, or an octave. Even though this patch is fairly thick, it works well with chords (see Web Clips 1 and 2).

Organic Alternatives

The most obvious way to build an organlike sound is to use the Harmonia processor on the Mult tab, and the factory preset Organ Sines 1 does just that. But Omnisphere's ring modulator, because it is polyphonic and offers keyboard tracking, provides a quick, flexible, and less CPU-intensive alternative.

Starting with the default patch, activate both Layers in Synth mode and set their waveforms to Sine. Activate each Layer's ring modulator with a sine-wave waveform and set the Layer A and B Frequency sliders to 0.333 and 0.750, respectively. (All multiples of 0.250 and 0.333 produce musically useful ring-modulator sidebands.) The Depth sliders control the level of the sidebands relative to the fundamental: full left for no ring modulation and full right for no fundamental. These sliders make good MIDI CC targets, letting you dial in the fundamental and sidebands.

Hard sync is a nice addition to this patch; its sound is still organlike but has more bite. Try mapping MIDI CCs to both Layers' Hard Sync sliders and moving Layer A's Shape slider full right. Pan the Layers slightly apart. Click the Link button on and turn the Analog and Phase knobs up as well, then click the Link button off. (Using the Link button is a quick way to make the same adjustment to settings on both Layers, which is also handy for envelope settings.)

You can use host automation along with MIDI control, but unlike with most plug-ins, you need to set up automation targets manually. Omnisphere presents automation slots (how many depends on the plug-in host), and the first eight are mapped to the eight Multi part levels. To automate any other knob or slider, right-click on it and choose Enable Host Automation from the contextual menu. The knob or slider will be assigned to the next available slot and accessible in your host's automation setup (see Web Clip 3).

Len Sasso is an associate editor of EM. For an earful, visit his Web site