Review – Predator 2 from Rob Papen


Predator 2 is latest synth offering from the prolific Rob Papen; following the original Predator almost ten years later, we think you’ll find it was worth the wait.


by David Baer, Jan. 2017


In this review of Rob Papen’s new software synth, Predator 2, we will assume the reader is new to the instrument and has no familiarity with the original Predator synth.  But just as a bit of background, let’s start by talking about that original instrument which originally appeared on the scene almost ten years ago.  That was a fairly conventional subtractive synth: three oscillators, a full-capability filter and another not-quite-so-robust filter, modulation effects and an arpeggiator.  While somewhat conventional, it was nevertheless a real workhorse whose factory preset list grew into the thousands before it was all over. 

Predator 2, being backward compatible with the original, leaves the starting gate with an already more-than-generous number of sounds on board.  The original Predator had a fairly straightforward interface with all controls visible on the main panel.  Predator 2 has many more controls, a larger main panel and a section of that main panel that is a tabbed area containing a wide variety of further control options.  Make no mistake, Predator 2 is a deep and powerful instrument.  So, let’s see why.

But one quick note first.  Right before publication deadline, an upgrade version of Predator 2 was released that included several new features and an alternate skin.  The UI image at the top of this article uses the new “white” skin.  The remaining images seen here use the default darker skin.



A big part of the Predator 2 story, and a big part of the enhancement story as well, are the oscillators.  In the original, there were three, all them having 128 single-cycle waveforms available for playback.  We still have the three oscillators, but have they ever gotten more sophisticated.  However, before we get into details, we need to discuss terminology.

In modern synth discussion, the term “wavetable” synth has come to imply an instrument that can load an array of single-cycle waveforms and play them while morphing seamlessly (or not) through them.  The position in the array is often controlled with modulation, offering all kinds of possibilities for animated sound.

However, an early use of the term “wavetable” was to describe a mechanism by which a single cycle waveform could be represented as data.  Wavetable synths (using the original meaning of the term) have been around a lot longer than wavetable synths using the more recent connotation.

This is important to understand because the documentation of Predator 2, documentation that is generally quite good by the way, does use the earlier meaning.  But Predator 2 actually can do morphing between single-cycle waveforms in an array, so it can behave at times like a wavetable synth in modern parlance.

Confused?  Please don’t be.  A Predator 2 wavetable means a single cycle of a waveform.  A “wave set” or “wave table set” means multiple single cycles in an array accessible to an oscillator.  As long as that is clear, the documentation will make sense even on the first reading.

To the right you see one of the three oscillators.  All three oscillators are much alike, but Oscillator 1 is a little different, lacking the FM and Sync options found in 2 and 3.  Seen to the right is Oscillator 2.  Let’s start by discussing waveforms.  An oscillator can load one or two individual waveforms.  All Predator (1) presets use only the one slot.

There are 128 factory waveforms supplied, and there is a provision for user-defined waveforms as well.  If two individual waveforms are loaded, the oscillator can morph between them (under control of the topmost oscillator knob).  The available waveforms have multiple variations of standards like saw waves, square waves, composite saw/square waves, and so forth.  More than half of the waveforms are labelled Spec nn, “Spec” being short for “spectral”, I presume.  These are all over the map and are arraigned somewhat arbitrarily.  Below are images of Spec 50, 51 and 52, just as a randomly selected sample.





We can load two waveforms in A and B slots in the oscillator.  When two are loaded, then there are five modes of transitioning from the A wave to the B wave that will give different sounds during the transition based on which mode is employed.  For example, L Morph does this (quoting the documentation):

The Partials of Wave A & Wave B are combined by Partial number. At 0% only Wave A’s Partials are used, and as you increase the Morph Amount more of the lower Partials of Wave B are used to create the Oscillator’s Wave.

Rounding out the options are the possibilities for Ring, Frequency and Phase modulation, wave B being the modulator.

Wave sets can be a collection of up to eight user defined waves.  We’ll get to how those are defined momentarily.  One can specify Wave Set for Wave A in any of the oscillators.  In this case, Wave B is replaced by two number fields in which one defines the starting position in the wave set and the ending position.  When a wave set is loaded into the oscillator, morphing can be done either stepped (discreet, abrupt transitions between the waves) or morphed (seamless, gradual transition).

Now, let’s take a brief trip to one of the tabs in the lower middle of the UI in order to discuss a related topic: how user waves are created and modified.  To the right you can see three subpanels.  In the middle one the level and the phase of the partials can be specified via mouse interaction.  Rob Papen has announced that enhancements for user wave creation will be forthcoming that include a larger editor for drawing user waves and the ability to import user waves from external files.  The third panel can be used to simply browse all the factory waveforms and check out what they look like.  Of course, any of the factory waveforms can be used as starting points from which to construct custom user versions.

One final point regarding user waves: there is but one set of these accessible.  Furthermore, when needing an LFO with a custom waveform, that must come from one of the eight user wave slots.  Normally this should not be a limitation.  You don’t need eight separate waveforms for interesting multi-wave morphing to be achieved.

Getting back to the oscillator itself briefly, there are a few things we haven’t touched upon: unison mode, symmetry, symmetry modulation, sync, FM, sub-oscillator and a few other goodies.  For details see the documentation.  All in all, you will probably find the oscillators to be extremely capable.  They don’t do sample playback (for that check out Rob Papen’s Blue 2 synth), but they do a very great deal and offer many, many options for creative sound design.



The next obvious things to consider are the filters.  To the right we see the main panel area devoted to filters (click on the image to see it full size).  There are two main filters that can be one of twenty-seven analog-modelled types, and there’s also a completely independent resonant high-pass filter.  The two main filters work in series on the combined output of all three oscillators (an exception here in a moment).  We have detailed control over either filter by selecting the “1” or “2” option.  Note that each filter has its own dedicated envelope.  When “1+2” is selected, we see a limited view of both filters making it easy to adjust cutoff and resonance of both with the visible controls, but individual settings specified in the detailed individual view is maintained.

The filter options include two different models that have quite different character for a good assortment of LP, BP and HP varieties of varying slopes, plus there’s a handful of specialty types like comb and formant filters.

The filter controls should be pretty much self-explanatory.  Keytrack ranges from -100% to none (12 o’clock position) to 100% (fully clockwise).

Filter 2 has a couple of extra options: Split 1 and Split 2.  These are not mentioned in the current documentation, but presumably the quote from the original Predator documentation is still valid:

Split 1 In this mode, Filter 1 and Filter 2 are in parallel, so that Filter 2 has the same properties, such as envelope, filter tracking etc, as Filter 1. The only difference is that Filter 2’s frequency can be altered independently from Filter 1’s.  Using Filter Pan in the advanced screen, you can pan Filter 1 and Filter 2, from both being centered, to Filter 1 being panned left and Filter 2 being panned right.

Split 2 In this mode, Oscillator 1 goes into Filter 1, Oscillator 2 goes into Filter 2 and Oscillator 3 goes into both Filter 1 and 2. Filter 1 and Filter 2 are also in parallel and joined, so that Filter 2 has the same properties, such as envelope, filter tracking etc, as Filter 1. The only difference is that Filter 2’s frequency can be altered independently from Filter 1’s.  Using Filter Pan in the Advance screen, you can pan Filter 1 and Filter 2, from both being centered, to Filter 1 being panned left and Filter 2 being panned right.

Pre-filter distortion is available (post-filter distortion is also available, but that is to be found in the Amp sub-panel).  A variety of distortion types are on tap, and in general I find the distortion quality to be extremely tasteful and useable.  With many synths, only the lower ranges of distortion amounts are appropriate and everything else is over the top.  To my ears, Predator 2 has perfectly nailed this one in both places where distortion can be added.

This is also a good time to bring up a simple but entirely welcome feature in Rob Papen synths that I wish all developers would embrace.  The envelopes have the usual ADSR components, but there’s one more: the ability to have the level of the sustain portion of the envelope gradually fade or grow.  This means that one can have a rapid attack and decay to some initial sustain level, and then a further, more gradual reduction while the note is held.  For both amplitude and filter cutoff, this can more closely imitate real-life acoustic behavior in various types of instruments.  And so, the filter envelope benefits greatly from this thoughtful but all-too-seldom-found capability.


The Amp and Play Sections

The Amp subpanel is almost entirely self-explanatory.  The only unusual feature is the EQ Mixing control.  What’s going on here is that one can dial in one of several pre-defined EQ settings (aptly named for pad, lead, etc.).  To see what the factory EQ presets look like or to define a custom EQ setting, we return once again to the tabbed area in the lower middle area of the main panel.  Here we find a three-band EQ control that also supplies a high-pass and low-pass standard filter at the extremities.









Play Mode also has typical controls for mode (poly, mono, legato) and portamento.  Unison operation is also pretty standard.  The Chord function works in conjunction with a center tabbed panel feature for defining one-note-pressed/multiple-note-heard capability.  Check the manual for full details of this feature.



FX, Modulation, Arp

Up to three effects can be inserted into a preset.  There is a plentiful selection of 28 quality effects on offer.  The effects include delay, chorus, flanger, distortion, dynamics, and so forth.  The panel knobs change according to selected effect.  There’s nothing out of the ordinary here – it’s all good, though, and you should find little, if anything, to be found lacking.



The heavily-used modulations are all provided for directly on the main UI (envelope control over filter cutoff, for example).  For everything else there’s a twenty-slot modulation matrix.  Predator 2 doesn’t offer a drag-and-drop modulation definition capability that’s becoming increasingly common, but the on-board modulation matrix is serviceable enough as is.

Not shown, but still important, is the sub-tab of the lower-middle UI section for defining LFOs and envelopes.  There are four of each that can be used to modulate a whole host of targets.  The LFOs can be per-note (poly mode), tempo-synced or free-running.  Assignment to targets is done in the modulation matrix.


The star of the modulation show is the XY controller.  This is becoming a standard feature in all the recent Rob Papen synth releases – the one in Blue 2 is essentially identical.

We not only have a manual control that can modulate up to four parameters each for the X and Y dimensions, we have a very sophisticated auto-play feature that is much better experienced in a video demo than words … but I’ll try.  In the screen-shot above, we see a spiral pattern that defines the path a note-response will take. Starting at the top-middle, a note traverses the path, continually curving inward until it terminates at the center (the spiral figure shown is one of the factory presets available).  Each note gets an individual and independent “carrier” to take it along its way in the animation path.  While there are some nice (and in some cases very elegant) presets to call up, the user may, of course, define his own.

In the XY-controller image above, we see both the controller and its associated modulation mapping sub-tab in the tabbed lower-middle section of the UI.  The controller area on the left is always visible on the main panel, even if the modulation sub-tab is out of view.

The arpeggiator is full-featured, as is aptly demonstrated by a number of great presets.  I won’t go into details here, but there’s much to like, if arps are your thing.





Everything Else

As stated earlier, there is an ocean of factory presets that come with Predator 2, over 5500 of them (which may be some kind of world record for a single instrument!).  Granted, most of these are carry-overs from the original Predator, and, as such, don’t take advantage of the marvelous new oscillator features, etc.  But who’s complaining when there are so many good ones?  This being a Rob Papen offering, it’s almost a certainty that much more factory content will emerge over time, even if version-2-specific presets are not all that prevalent in this initial release.

Predator 2 moved away from the patch-bank organization of the original, so upgraders will have a slight adjustment.  But import of version 1 presets is accommodated, so no problems should exist on that front.

Fortunately there’s a new browser for finding needles in the preset haystack, see below:


While the main UI is relatively straightforward, if a little crowded, there’s an Easy page to limit the displayed controls to only those most frequently used.  This will be especially appreciated by users who limit their usage to light preset-tweaking.


There’s more here that we haven’t had space to cover, but hopefully we’ve hit all the most important points.


Is Predator 2 for You?

Well, what’s not to like?  Seriously, this is one gorgeous-sounding, highly-capable and intriguing instrument no matter what your genre of music production might happen to be.  In looking at the preset allocation among the various categories, you might be tempted to infer that Predator 2 is aimed at dance/club music production, but there just happen to be a lot of dance-oriented presets (many of which are quite suitable for other uses, by the way).  This is an extremely versatile instrument that has no genre boundaries.

Predator can be purchased from numerous music-software retailers or directly from Rob Papen here:

The listed price is $149 USD.  Upgrades from Predator 1 are a modest $49 USD.  Potential buyers may also wish to purchase the entire collection of Rob Papen instruments and effects by buying the Explorer 4 bundle.  This lists for $499 USD, a reasonable price given how much is in it.  SoundBytes presented an overview of all the synths in the Explorer 3 bundle that can be found here:

Sales do happen with Rob Papen products, so patience will probably be rewarded.  Furthermore, Explorer purchase price goes down for those already owning other Rob Papen products.  See the website for all the details.

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