The world the audio signal inhabits is purely analog. The oscillators rely on voltage, not samples or number-crunching, to generate their waveforms. The filters use analog Curtis chips, just like the Prophet-5. However, the Prophet ’08’s matrix modulation, tempo-synced LFOs, and the four-track step sequencer are from the digital world. Unlike Dave’s Evolver line, the ’08 has no digital conversion in the audio signal path, which the Evolvers require because they have digital oscillators alongside their analog ones, not to mention digital effects. The Prophet’s oscillators are digitally controlled, meaning that a microprocessor oversees their settings for stability, but that’s it. If a computer tells your front porch light to go on at 8 p.m., that doesn’t make light from the bulb “computer-generated” either.

The ’08’s sound engine consists of two oscillators, a fully resonant filter (with FM input from the oscillator section), voltage controlled amplifier, four LFOs, three envelopes, and a four-way matrix modulation section for additional routing. Now, take the above voice architecture and double it, because you can do splits and layers within a single preset. So, every sound can have up to four oscillators, two filters, and so forth, right out of the gate. Tranceheads can (and will) take this to extremes, whipping up 16-oscillator mega-leads by simply pressing the Unison button.

You access the second sound by pressing the Edit Layer B button. If neither splitting nor layering is active, this button simply switches between two sounds, turning one patch into two. When both layers are active, you only get four notes of polyphony, and with splits, voices are not dynamically allocated; you simply get four voices for each part. It’s doubtful you’ll need more — when dealing with analog sound that’s this fat, the rules are different. Heck, some modern analog synths have one voice, and nobody complains.

To top it all off, you can route layer B to the Prophet’s secondary stereo outputs, letting you run a preset’s two sounds through different outboard mixer channels and effects. In fact, you’ll need outboard gear to add effects such as delay or reverb. While this seems stingy if you’re used to the extensive effects menus in today’s digital keyboards, it’s a purist design choice here: Building in these effects would have meant converting the sound to digital, then back to analog as it hit the outputs.

OSCILLATORS

Each oscillator has four waveforms: sawtooth, triangle, saw/triangle hybrid, and adjustable pulse width, which can be used for everything from reedy sounds to bold square waves. The saw/triangle is a nice touch, as it has more body and less fizz than a regular saw, making it good for blending low end beef into a sound when the filter’s cutoff is wide open. If you want more highs, the ...

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