eXploring the Marvels of Rob Papen Synthesizers


Rob Papen is a prolific developer of synths and other audio production software.  We survey his extensive synthesizer catalog herein.

by David Baer, May 2016


Rob Papen must be one of the busiest synthesizer and FX developers around, given the number of instruments FX modules bearing his name.  Up until now, we have given only scant coverage to Papen products in SoundBytes Magazine, but that’s certainly not due to having taken any editorial position.  Chalk it up, once again, to too many synths, too little time.  Hopefully we’ll begin to correct that oversight in this article in which we will take a tour of the seven synths that currently comprise his catalog of software instruments.

These instruments range from the fairly conventional to the unique and wildly innovative.  Many of them clearly are oriented to production of contemporary club music.  But no matter what you’re preferred genre is, there’s a good probability that there’s at least one of them for which you will develop serious lust.  The complete synth offerings, along with all the Papen effects (which we’ll have to look at some other time), are packaged into the eXplorer III bundle.  Two smaller bundles aimed at EDM and “Urban” production are also available.  See the URL at the end of this article for particulars.

Because we are looking at all the instruments here, the individual overviews will be necessarily brief.  Be aware that Mr. Papen has produced a series of very informative demo videos available on his YouTube channel (once again, google is your friend).  They should be more than sufficient to provide the necessary knowledge for the prospective customer on whether or not a particular instrument will be of use.  Also be aware that any of these instruments can be downloaded as a demo with more than enough time on the meter to adequately evaluate it in a thorough manner.


Before We Start …

First, several observations that apply to pretty most or all instruments are appropriate before we dive in to individual coverage.  The first is to note that the documentation is uniformly quite good – very clear, reasonably concise, and well-organized.

Many, and perhaps eventually all, of the synths are compatible with Native Instruments’ NKS system for integrated interaction with NKS-compliant controllers.

The next point is that the factory content is more than generous in all cases.  If you are a preset-only type player, you won’t feel a lack of possibilities.  If you like to tweak, there’s a wealth of presets from which to begin your creative explorations.

Finally, there’s one small feature that is seen throughout – one that will be greatly appreciated by thoughtful sound designers.  It’s extremely simple, yet it’s one rarely seen elsewhere.  ADSR envelopes are not particularly good at reflecting the nature of real sound for instruments that are plucked or struck (e.g. harps, guitars, pianos, vibraphones, etc.).  With these we have an energy-laden initial impulse, well-served by the AD part of the ADSR envelope.  After the impulse, the sound relaxes to a steady state that slowly loses energy, in total, but also normally with higher partials decaying faster than lower ones.  The S portion of the ADSR shape does not serve us well here. 

Mr. Papen had the wonderful insight to provide a Fade capability for the S portion of the envelope.  Applied as an amp envelope, we have a natural dissipation of overall energy.  Applied to filter cutoff, we can cause higher partials to attenuate earlier than lower ones.   As I said, extremely simple and elegant … so why doesn’t everybody do this?

OK, with that out of the way, let’s dive right in.  Since there’s no logical way to order these, I’m just going to cover them alphabetically, which by coincidence, puts my two favorites at the top of the list.




Blade is flat-out crazily innovative.  It’s an additive synth, but it approaches additive synthesis in a vastly different way that say, Harmor or that other well-known additive synth that went over to the Dark Side and which is now dead to me.   :mrgreen:  The mechanisms by which additive sound is engineered is one way in which it’s highly innovative.  The other is that is has a programmable XY controller that is a principal modulation source of great capability (one that we’ll see in Blue2 in a moment, and probably in more places in future Papen products).

In the UI image above, on the left is a section called the Harmolator.  This is where the additive parameters are set which dictate the basic current sound.  The documentation requires nine pages to fully explain all that’s going on here, so I can only scratch the surface here about how this all works.

But, for example, we have a control called Even/Odd.  Not surprisingly this can be used to emphasize even partials when turned counterclockwise and odd when turned the other way.  Significantly, all these knobs invite modulation, which is where the XY controller comes in.  The XY controller is not the only modulation source in Blade; there are numerous others.  But it is the main one and especially adept at animating the additive properties of the sound.

The controller can be driven by mouse movement or can be slaved to MIDI controllers.  But it can also be programmed to move on a predefined path, synced to host tempo if desired.  Control can be polyphonic, with each new note-on getting its own position in the grid and independent positional influence.  The multiple dots in the UI image illustrate a polyphonic response in progress.

There is much more in Blade, of course.  We have distortion, a filter, envelopes and LFOs, onboard FX and more.  I could easily spend an entire article (a lengthy one at that) exploring all that’s here.  In fact, I could fill up an article just talking about the Harmolator and another about the XY controller.  We’ll have to stay at a high level, though, since there are so many instruments to cover.  But if you are intrigued by what you’ve read here, be sure and search for some excellent demo videos made by Rob Papen that can be found on Youtube.  I trust that you know how to track them down via google.

Blade sounds rather digital, which is typical of every additive synth I’ve ever encountered.  But there’s a vast range of sound possibilities.  Papen includes Blade in its EDM bundle, so you have an idea of where at least some people think it fits in the music production sphere.  But really, it’s capable of a wide range of digital audio tricks, from delightful, fidgety electronica to sedate, spacey evolving soundscapes.  And sound design is great fun, even for the beginner.




And now the synth that I honestly believe has something for everyone, the marvelous, the amazing, the brilliant Blue-II (sometimes aka Blue2).  When I first saw the demo video of this instrument, I thought to myself that this one would probably go immediately into my top five synth list if I ever got my hands on it.  And it has certainly done just that.  I cannot imagine anyone not finding good use for this instrument, irrespective of what musical genres they produce.

Blue-II is awesomely deep and capable.  To begin with, we have six oscillators that can provide subtractive functions via a huge collection of factory supplied waveforms, both single-cycle and sample sets.  But it can also do FM.  There is wave shaping and wave sequencing on hand.  But at the end of the day, what’s important is the sound, and, oh, what breathtaking sounds can be had here, as the immense collection of factory presets ably demonstrate.  Blue II is capable of much analog-style warmth.  The sample sets include some of the most gorgeous strings, choirs, and other pad-friendly sounds you can imagine.  At the other end of the spectrum, if it’s brutal, raw power you’re looking for, there’s plenty of that on tap as well.

There are a myriad of additional features that are worthy of your attention.  First, we have the XY pad capability similar to that in Blade.  But in Blade, the modulation destinations are hard-wired.  In Blue2 they can be set on a per-preset basis.  The XY controller can also be used to simply control the mix of the first four oscillator levels.

There is a four-slot FX section (example seen to the right) with variable routings into which a selection from a list of 35 excellent effects.  For filters, we have a selection of analog-modelled types, 27 to be exact, again with flexible routing options at your disposal.  There’s a very capable arpeggiator.  There’s also a sequencer with which can be used in not only the usual fashion but for wave sequencing as well.  There are modulation possibilities beyond counting.  Really, I don’t think this instrument could be adequately covered in a full single review, there’s just so very much on board.

 As I stated earlier, there’s really no type of music imaginable that could not make excellent of Blue II’s many, many competencies.  We have barely scratched the surface here.  I would particularly recommend the Youtube videos on this one.  But a word of caution – if you watch, you will almost assuredly want to buy this marvelous instrument.




Next we look at Predator, which is a fairly conventional subtractive synth.  But we won’t spend a lot of time on this one because Predator 2 (or will it be Predator II?) is in the pipeline and is expected to be available towards the end of summer this year.

Predator is included in both the EDM and the Urban bundle, so that gives you an idea of where Mr. Papen thinks it fits into the music production picture.  Likewise, if you examine the bank names, a significant majority of them are clearly dance/club-themed.

But really, we have in Predator (1) a fairly conventional subtractive synth with a few extras.  There are three oscillators that have 128 typical synth waveforms on tap.  A symmetry control allows for manipulating wave shape in a manner that can be modulated.  The second and third oscillators can be synced to the first in classic fashion.  There’s limited FM and other oscillator cross-modulation capabilities.

A single filter is on hand with the usual varieties from which to select that also include a few specialty-type filters like formant.  There’s an arpeggiator, two LFOs, two envelopes, and a limited modulation matrix.  Three FX slots can be filled with a variety of several dozen FX types.  Notably, a vocoder effect is one of the options.

One interesting feature is the morph capability.  You can select two presets and specify a morph level (e.g. one-third preset A and two-thirds preset-B), hit a generate key, and a new preset will be created having the desired blend.

By no means have I wanted here to damn Predator with faint praise.  It’s just that with Predator 2 so closely at hand, that upgraded version will no doubt have many advances compared to its predecessor.  We will be reviewing Predator 2 in some detail later this year, so stay tuned.  Given the power and sophistication of Mr. Papen’s most recent releases, we look forward to Predator 2 with great anticipation.

At the time this is being written, people who purchased Preditor in the last few months will get a free upgrade.  But it is now on sale at a significant discount, so those purchasing it before version 2 is released will pay what everyone else will for an upgrade, $49 USD.  If you did not buy it directly from the Rob Papen web site, save your receipts.




Punch is Rob Papen’s take on the drum machine.  I must begin with the disclaimer that I am not a drum guy and cannot offer much in the way of insightful observation on any software having to do with drums.  Too bad SoundBytes Magazine’s drum expert Suleiman is not writing this section, but I’ll give it my best effort.  That said, a trip to YouTube to see Mr. Papen demo it himself would be worth your time if this sort of instrument appeals to you.

Actually, there are two Punch instruments: Punch and Punch BD.  The former offers full kits and the latter allows stacking up to six bass drums (thus the “BD” in the name).  Of each of these, there are two versions: one in which everything is mixed and output to a single audio output and one in which each individual component is output to its own audio output, allowing one to control the mix in the DAW.  Punch is pictured above and Punch BD is pictured immediately below.


Punch supplies both synthetic drum sounds and sampled ones.  Users can furthermore supply their own samples to round out their kit.  There are filters and FX modules on board to introduce further excitement.

This being a drum machine, there is, of course a sequencing capability on board.  It looks pretty powerful to me, having watched the demo video.  But I encourage those sufficiently interested to view the video themselves.  I am not in a position to suggest how Punch holds up against the many other virtual drum instruments out there.

Not surprisingly, both Punch and Punch BD are included in both the EDM and the Urban bundles.




The story behind RAW is told at the beginning of the user manual:  At the Dutch Dancefair in 2014, DJ Promo (aka producer Sebastian Hoff) and DJ Free-k (aka producer Freek Vergoossen) approached Rob Papen with the idea of a synthesizer that focused on distorted sounds with an easy to use interface and that sounded great.  Rob Papen invited the DJs to his studio for a brainstorming session resulting in a list of must-have features and tools for a brand new synth.

Hmmm, another genre about which I am basically clueless!  Maybe this alphabetical order notion wasn’t such a hot idea after all.  :mrgreen:   Nevertheless, here goes …

RAW is all about distortion (big surprise!) and rhythmic distortion, at that.  It has many features dedicated to the pursuit of this goal.  There are several surprises here, or at least, surprises for me.  The first is the elegance in the design of something devoted to brash, chaotic mayhem.  I risk sounding like a broken record in recommending the YouTube video in which Mr. Papen demonstrates the instrument, but I do recommend just that.  Even if you have little interest in something along the lines of a DJ-ing instrument, you may find it interesting to just observe the thinking that went into the design.  As I said … surprisingly elegant!  The second surprise is that although most of the content lives up to the stated purpose of the instrument, there are some gems of more conventional synth patches to be found throughout the factory content.

There are two oscillators that have a small set of typical waveforms on tap and provisions for user-supplied waveforms.  Much is conventional here, like PWM and Sync (osc. 2 to osc. 1).  What’s different from convention is the control marked RAW.  This controls the level of phase distortion of the wave.  The XY grid to the right controls the amount of this distortion to the positive part of the wave (X position) and negative part (Y position).  The XY grid has the programmed movement capabilities we’ve seen in Blade and Blue II, but in this case that which is controlled is just the RAW distortion applied to the wave.  An LFO can also be brought into the picture for further movement of X and/or Y position.

We also have one filter, an amp section with no surprises, an LFO, and two EQs (pre and post-FX).  There’s a limited mod matrix.  There’s also an arpeggiator.  And of course there’s more distortion – three kinds to be precise.  We have a wave shaper, a low-fi unit and a multi-distortion module offering tube distortion, fuzz, rectify, and much more.

If you’re a bit bewildered about what sort of things for which DJs might use RAW, never fear.  There are loads and loads of presets designed by actual DJs.  So just pick up RAW, start calling yourself something like “DJ Kalesmoothie” and you should be good to go … DJ on, dude!




RG is a software instrument to be used to create guitar grooves, but it is not a guitar emulator along the lines of, for example, AAS’s Strum instrument.  The basic sounds are created from samples of strummed chords.  We have several models: electric, steel 8th, steel 16th, distorted, muted low and muted high.  The two steel varieties are similar but intended for slower (8th note) and faster (16th note) rhythmic speed.  Distorted plays power chords (no triads, just octaves and fifths in a chord).  The two muted varieties just play a single note, and it’s not clear to me what their purpose is (and the documentation is silent on this point as well).

The user interface might look a bit imposing, but this is actually a very straightforward instrument.  In the upper left we select the guitar model and provide values for loudness and decay speed for three different strokes: down, up and ghost (palm-muted strokes, I believe).  The large grey area are modules the signal flow passes through: filter (with LFO and envelope), amp, EQ, and a three-slot FX bin.  Limited modulation is present, but not needed nearly so much as would be the case in a more conventional synth.  The sounds produced can be very close to the real thing or can be made unrecognizable, depending on the use of the filter and FX.

The bottom grid is the sequencer.  Up to 32 steps can be programmed, specifying up, down, ghost or glide strokes at each step.  Only the electric model supports the glide (starts down a semi-tone and does an upward portamento).  There are two sequences that can be programmed called A and B.

The way sequences are triggered are as follows.  Each note in a four-octave range will cause a chord to be played in the sequencer.  C1 (where C3 is middle C) through the B above will play major chords using sequence A.  C3 through the B above will play major chords using sequence B.  The C2 octave triggers minor chords in sequence A and the C4 octave in sequence B.  If the model is distorted, then major and minor is not a factor (no thirds).

There you have it.  This one is very simple to understand and takes little time at all to pick up.




Last but not least we get to SubBoomBass, a synth dedicated to producing bass sounds.  Oddly, this one is included in the Urban bundle but not the EDM bundle which would be the first place I’d expect to see it.

As a synth, SubBoomBass is pretty conventional and not especially full-featured.  For example, there are only two oscillators (each having a sub oscillator, however).  What imparts the bass specialization capability are the wave forms and samples included for use in the oscillators.  In addition to several dozen synth waveforms, there are several dozen sampled sounds from both bass instruments and lower-frequency drum/percussion instruments.  And there is a crazy amount of factory presets that make good use of them all sooner or later.

The oscillators are pretty much what one has come to expect in a Rob Papen synth.  Each has a main oscillator and a sub, which can use either a sine or square wave.  In addition to symmetry and PWM, we have PWM for the square wave of the sub oscillator (but not the sine).    Oscillator 2 can be slave synced to oscillator 1 and can be frequency-modulated by it as well.

There are two filters, but only one of them has the expected modulation options.  The filter types are all the usual Papen suspects.  The second filter has only a cutoff control.

A good collection of FX are available to place into two FX slots.  A sequencer is on board offering up to sixteen steps and a surprising amount of sonic variety can be had using it, which can be seen by auditioning a number of the factory presets that use it.

So there you have it.  You could get much the same results with a conventional subtractive synth, but the available oscillator wave forms and samples really supports the bass intent.  If you are into synth bass, the factory presets should keep you well-supplied for a very long time.



Prisma is a new (in fact not yet released as I write this) plug-in that will be free and of interest to owners of any Rob Papen synth.  It is a rack into which up to four Papen synths can be loaded for a stacked sound.  “What’s the big deal?”, you might ask – “You could just as easily do that in your DAW”.  Well, there are several reasons why this will be advantageous to have and use.  But the easiest way to discover why you’d want this is to view the ten-minute video available at the Rob Papen web site (URL below) that shows what it can do.

Basically there are two reasons that I think the owner of one or more Papen synths will want Prisma.  One of them is that it offers a single set of controls that can be used to adjust behavior of the loaded synths in a coordinated fashion (e.g., raise filter cutoff in two of them while lowering it in two others).  But, as with all Papen productions, there will probably be a wealth of presets.  These will be of greatest advantage to those owning the whole collection of synths.  But even if one only owns Blue II (and, really, I cannot imagine anyone who would not want to possess this glorious instrument), there are some great ways in which to employ Prisma.  Once again, just look at the video demo to have your appetite whetted!

I saw this demoed at NAMM in January, and there have been some additional features added since that time that make it look even more exciting and definitely worth the wait.  Prisma should be available by the time you read this or very shortly thereafter.


Is eXplorer III for You?

If you’ve read this entire piece, you’ll know that the Rob Papen synth collection will most certainly be of interest to producers of club/dance music.  There’s much goodness for producers of innumerable other genres, but owning the entire collection makes the most sense if your thing is club/dance music.

The eXplorer bundle lists for $599 USD.  But there’s an easy and obvious way to get it any time for $399 by making two purchases rather than one.  If you can’t figure out how this works, you probably don’t deserve the savings and probably should not be allowed near a computer in the first place.  But on top of this, additional discounts are not uncommon.  A sale offering an additional 20% off has just ended, for example, so a little patience in timing your purchase will probably be well-rewarded.

Now, if we are talking about getting the entire Rob Papen synth collection (plus five fine FX plug-ins to boot) for something in the neighborhood of a bit less than $350, this is a strong value proposition.  There are some high-end individual synths that cost more which would be hard pressed to deliver the complex and exciting sounds which are soon to be available from the eXplorer bundle once Prisma is added to the feature set.

If your thing is not club/dance, you should nevertheless check out Blade.  It’s a most unique instrument that offers not only great sounds but a lot of entertainment value if you like to play around with sound creation.  And then there’s Blue II – oh, what a masterpiece.  Just find a way to acquire it – I guarantee you won’t end up blue if you do!

More information and purchase here:


Rob Papen products are also available from a number of online retail outlets, sometimes at advantageous prices.




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