Image Line Ogun

Click thumbnail to open full-size image in new window.

PROS

CONS

INFO

Click here for original audio example by Jim Aikin.

OGUN: NEED TO KNOW

What kind of sounds does Ogun make? Metallic sounds, which can range from a struck xylophone or gamelan instrument to scraped or bowed “metallophones” that exist only in your imagination.
Will it do basses, leads, keys, and pads? It can be coaxed into producing those types of sounds, but they’ll still have some Ogun flavor. With a little tweaking, the default patch turns into a decent Clavinet.
Is there aliasing? Not that I could hear. The additive engine seems to be anti-aliased very well.

Coolest sound design feature: Ogun will analyze and re-synthesize samples. The results may or may not come close to the original, but you can edit the timbre in amazing ways. I got nice results re-synthesizing some tabla hits.
Coolest experimental music feature: A switch can link MIDI key number to random seed 1. For most sounds this destroys the chromatic scale, producing a sort of prepared-piano effect.
OS and plug-in format stuff: Ogun runs on Windows XP or Vista as a VSTi (2.4) plug-in. It also runs natively in Image-Line FL Studio.

Fresh ideas in synthesizer design are rare. Ogun is a welcome exception to this rule. It doesn’t sound like anything else — it does metal. No, I don’t mean screaming guitar rock. Ogun creates the sounds of cymbals, gongs, and the bizarre metallophones of your imagination using a unique form of FFT-based additive synthesis. FFT stands for “fast Fourier transform,” and in case you didn’t major in engineering, it’s a way of doing math on the sine wave components of a sound that can generate thousands of harmonic overtones at once.

Additive soft synths tend to work a computer pretty hard, but Ogun was fairly kind to my 2GHz Core 2 Duo PC. Five settings in the preferences menu let you balance sound quality against CPU usage.

The only weirdness I spotted in version 1.0 was that you couldn’t save your presets so that they show up in the menu. Using the VSTi version, I could save and load standard VST presets (with the .FXP file extension in Windows), but the factory presets have a different file format, and Ogun won’t save in that format.

HOW IT WORKS

This may read like a throwback to the early days of Keyboard, because it’s almost impossible to explain Ogun other than by listing a bunch of parameters with unfamiliar names and telling you what to expect when you adjust them. In order to program your own sounds — which you’ll want to do, as the factory sound set is small — you’ll need to learn some new concepts. The results will be well worth the effort.

In place of oscillators, Ogun has a pair of “seed values,” which are numbers between 0 and 9,999. According to the Help file, these “generate independent weightings for the harmonic spectra.” In theory, they provide a place for that FFT math to start. In practice, changing the seed by even one increment (say, from 971 to 972) generally has a very audible and unpredictable effect on the tone. To work with seed values, just adjust them until you hear something you like.

There’s also a crossfader for blending Seed 1 with Seed 2. Moving this with the mouse while a note is sounding has no effect until you let off the key and trigger the next note, but controlling it from a mod wheel or knob while you play can introduce subtle or radical timbral changes. Extremely cool feature: When Seed 2 is set to “- - - -” the generator is re-seeded at every noteon, which can give you small (or large) timbral variations from note to note.

Pushing up the Fullness slider adds more overtones to the sound; when it’s all the way up, the Seed values become irrelevant. This interacts with the Richness slider: When they’re both high, gunshot noise bursts are almost guaranteed. Again, you find good sounds by trial and error. At low settings, the Timbre Pre-Decay slider adds attack transients. Push the slider up and they’ll evaporate.

A multi-segment volume envelope is available if you need it, but because Ogun imitates struck metal objects, the main panel sliders for controlling the volume of a sound (and that sound’s timbre, to some extent, because some partials seem to decay more quickly than others) are for decay and release time.

The heart of Ogun programming is a set of 17 settings that you access via a pop-up menu above the central envelope editing grid. The first five of these, in the Articulation area, are volume, filter cutoff and resonance, pitch, and unison pitch deviation. Each of these can be controlled by an envelope, LFO, keyboard mapping (i.e. which note you’re playing), velocity, or the onscreen X-Y control pad.

That’s all familiar enough to synth fans — but then things get interesting. Parameters you can map to control sources (velocity, for instance) include timbre decay, timbre release, rotation, fullness, morphing, and EQ shifting. These have no envelope or LFO control, but keyboard note, velocity, or the X-Y pad can affect them. Morphing duplicates the Seed 1/2 slider.

The most straightforward way to use all these controls is to map a bunch of things to keyboard note and/or velocity, thereby creating a sound that is extremely responsive and varied as you play. By mapping EQ shifting to velocity, for instance, you can create the effect of a cymbal or bell producing different overtones as it’s struck harder or in different spots on its surface. By designing complex multi-segment maps for the keyboard, you can make it seem as if you’re playing several different patches in different zones — with each zone able to crossfade smoothly into the next.

If you’ve used Image Line Sytrus, you’ll recognize the mapping curve and envelope editing. Looping envelopes with rhythm grid snapping, editable segment curve shapes (including staircase and pulse shapes). Templates can be saved and loaded. The spice in envelope curve editing is a draw mode, which can add dozens of breakpoints quickly.

CONCLUSIONS

Ogun’s metallic synthesis is little too clean-sounding to be mistaken for, say, real metallophones such as gamelan percussion or glockenspiels, but the realism of a couple of the factory patches is quite striking. Think of this synth as a radically new way to produce sounds that are electronic but have a surprising amount of physical richness. Given the very modest price, Ogun is a Key Buy that’s almost too good to pass up.