Dave Smith Instruments Prophet 12: The Ultimate Hardware Synth?
By Francis Preve
Fri, 11 Oct 2013

Last spring, Dave Smith won a Grammy for his technical achievements. Aside from being the primary inventor of MIDI, Dave is the brains behind milestone technologies like the first programmable analog polyphonic synth (the Sequential Circuits Prophet-5), digital vector synthesis (the Prophet-VS), wave sequencing (the Korg Wavestation) and the first soft synth (Seer Systems Reality). With a résumé like that, what do you do for an encore? Release the Prophet 12, of course. Dave calls it the finest synth he’s ever designed. After spending some quality time using it, we think he’s being modest.


Four oscillators that include virtual analog, wavetable, FM, AM, and multiple hard sync options—plus sub-oscillator. Dual resonant lowpass and highpass analog filters. Extremely comprehensive modulation routing. Tons of realtime performance features. Dual stereo outputs. Two simultaneous synths can be layered or split. Sounds tremendous.


Not everyone can afford three grand for this experience. Unlike Poly Evolver, no step sequencers onboard.

Bottom Line

Not only is the Prophet-12 the finest synth Dave Smith has yet designed; it’s also the finest hardware synth for synth geeks currently on the market.

$3,299 list | $2,999 street



First off, the Prophet 12 (P12 for short from here on) is not a workstation. It’s a synthesizer for players who love synthesis. While its oscillators are digital, its filters and amplifiers are analog. While some purists might pause at the oscillators not being real analog, I think they’re missing out in this case. For one, the oscillators’ virtual analog waveforms are rendered so smoothly that even diehards will quickly forget that they’re listening to digital. Second, the P12 goes so far beyond analog capabilities that everyone will be too busy creating and playing amazing sounds.

The high-level architecture of the P12 is as follows: There are two supremely capable synths running simultaneously. You can layer them, split them, or have both play the same sound, either in monophonic unison or with 12-voice polyphony. Dual stereo outs let you process each synth differently and MIDI over USB lets the P12 quickly fit into studio rigs. There’s also a plethora of performance tools like two touch-strip sliders for realtime modulation, aftertouch as well as velocity sensitivity, and a pair of arpeggiators waiting to percolate as you play. As to factory presets, there are 792 to be exact.

But other synths can say a lot of the same things, so why’s the Prophet 12 so special? Because of its synthesis engine. As synthesizers go, this one is a Pacific Rim-sized sea monster. So let’s rip it open and dive inside the innards.


The Prophet 12’s digital oscillator section is the deepest and most flexible I’ve ever seen in a hardware synth. Even more impressively, its knobs are laid out in a way that makes it extremely accessible to new users. In addition to the de rigueur coarse and fine tuning knobs, there’s a clever array of parameters that all affect the sound in dramatic ways, regardless of the selected waveform. The sonic variety available in the oscillator section alone is so broad that I got lost in it for several hours before remembering that I hadn’t yet touched the analog filters.

Skating across the surface of the oscillator section, you’ve got 19 waveforms to choose from: Four classic analog waves (sine, triangle, square and sawtooth), 12 digital wavetable options, and three noise generators. Each waveform is affected by the Shape Mod knob in a pronounced manner. For the analog waves, this knob adjusts the duty cycle of each waveform. On a square wave, this knob adjusts the pulse width in classic fashion. On a sawtooth or triangle wave, it does a similar trick, but with vastly different sonic results. In simplest terms, the Shape Mod knob functions as a way to manipulate the structure of each waveform without getting all mathematical ’n’ stuff.

The digital waveforms are a brilliant implementation of Dave Smith’s revolutionary work on the Prophet-VS and the Korg Wavestation. When one of these waves is selected, the “Wave Right” and “Wave Left” options on the P12’s OLED display become active. From there, you can select two different digital waveforms. Then, using the shape mod knob, you can smoothly morph between the three waveforms’ harmonic spectra, yielding thousands of waveform permutations, depending on what you’ve selected.

The three noise waveforms are red, white, and violet. Here the Shape Mod works a bit like an EQ, allowing you to “tilt” the frequency spectrum of each. For newcomers, red noise has emphasized lower frequencies, violet noise emphasizes highs, and the classic white noise is more balanced. In practice, the Shape Mod knob can blur those lines considerably.

Remember, we’re still only talking about one oscillator here. There are four of these babies in the P12, plus a sine wave sub-oscillator that tracks the first oscillator. Taking everything up a notch, you can do much more than simply mix the oscillators. The P12’s oscillator bank also includes FM, AM and sync tools for all four oscillators.

In a manner that reminded me of Rob Papen’s brilliant soft synth Blue, the P12’s oscillators can do all kinds of sideband tricks that you just don’t see in hardware synths. Better still, despite the underlying complexity of the technology, the default implementation is pretty straightforward once you learn the basics.

With hard sync, the oscillators are all connected to each other in a cascading manner. That is, oscillator 1 slaves to oscillator 2, oscillator 2 slaves to oscillator 3, and so on, with oscillator 4 slaving to oscillator 1. The whole concept flows like a big circle, which is why Dave designed the front panel with a big silkscreened circle around the oscillator select buttons.

Frequency Modulation and Amplitude Modulation synthesis tools are configured in a very similar manner. In both instances, the lower-numbered oscillator functions as the carrier. Again, the “circle” topography holds: Oscillator 1 is the carrier and oscillator 2 is the modulator, which is then modulated by oscillator 3, and so on. If you’re familiar with FM synthesis, it’s easier to think of this implementation as reminiscent of algorithm 1 on Ableton’s Operator soft synth or on a Yamaha DX9. (I’d say DX7, but since the DX9 had four operators, it’s the closer analogy.)

If you want to go even further down the rabbit hole, you can use the P12’s modulation matrix—and we’ll get to that in a bit—to alter these modulation routings in even more complex ways.

Rounding out the oscillator tools are per-oscillator glide/portamento, key follow on/off, wave resetting (so the oscillators always begin “speaking” at the same point in their wave cycles), and the clever Slop parameter, which lets you dial in analog-style pitch drift in subtle to copious amounts.


The Prophet 12’s innovative “Character” section further sculpts the oscillator bank’s output with five unique parameters that operate on a per-voice basis before they hit the filter section. The parameters are as follows: Girth, Air, Decimation, Hack, and Drive.

The Girth and Air parameters function like a cross between shelving EQs and harmonic enhancers. In practice, these work a little bit like Aphex Aural Exciters, with extreme amounts of Air adding high-frequency sparkle. Cranking the Girth knob to max is also a bit like the Aphex “Big Bottom” feature, boosting low-end warmth in extremely musical ways. These two knobs alone will be a huge benefit for live performance, allowing keyboardists to EQ their patches before they hit the mixer.

The Decimation and Hack knobs are essentially an integrated bit-crusher, with Decimation modifying the sample rate and Hack reducing the bit depth of the oscillator output.

Finally, the Drive knob is a fantastic addition for more analog-style patches, adding overdrive and saturation enhancement to the overall tone of the oscillators. It’s worth noting here that the Drive knob interacts with the oscillators’ frequency modulation tools in an extremely intense manner, so if you’re dabbling with FM as you work and things start to spin out of control, double-check this parameter. In many cases, a little goes a very long way.

Next: Filters, Modulation, Envelopes, and more!
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