Log InCreate An Account
25% Off for 4Days04Hours23Mins45Secs(2 Jul 2022)
Blue II
What is it?
Operating System Availability
Operating System Latest Version
System Requirements
32 & 64-bits VST and 64-bits AAX for Windows 7/ Windows 8/ Windows 10
(Note: PC AAX for PT 12 or higher)
System Requirements
64-bits AU, VST and AAX, for OS-X 10.9 - 10.15.
License & Installation Method
Voucher / Code for redemption on other website
What does this mean?
For related news items, downloads and more please see the full KVR product page for
Blue II

Blue II delivers FM Synthesis, Phase Distortion Synthesis, Wave Shaping Synthesis and Subtractive Synthesis is one creative combination - "Crossfusion synthesis".

Blue has six oscillators which can be connected in various ways, two analogue style modelled stereo filters, an enormous range of processing and modulation options, sequencer and an incredibly powerful arpeggiator. Despite these heavy features, Blue is so easy-to-use thanks to its user interface and the innovative 'easy edit' page for quick sound changes.

This all brought together with over 2000 inspirational Rob Papen presets and more, covering a wide range of musical styles.


  • Six Oscillators modules which include Analogue, Additive and Spectral type waveforms. Osc. A and B offer PWM modulation and symmetry control. Oscillators can be combined in several ways using 32 different modulation routings in the Algorithm screen. Oscillators can have FM modulation or Ring modulation and can be oscillator hard synced. Each oscillator can be output to the filters, the effects or output as dry. Dedicated screens available in the LCD screen section for Algorithm selection, Phase distortion / Wave shaping settings and Oscillator Envelopes.
  • Two analogue modelled stereo Multimode filters, offering 6dB LowPass/HighPass, 12dB and 24dB LowPass/HighPass/BandPass/Notch, Ring, Comb and Vox (formant). Filters with panning, panning modulation options and pre-filtering distortion. Easy filter control by pre-defined modulation controllers like Envelope, Velocity, Keytrack and Modulation Wheel.
  • Nine Envelopes, AHDSFR type. Direct connection to the Oscillators volume, Filters frequency and main Volume amp to make sound editing fast and easy. Graphic and fader-control of Envelopes in one go. Dynamic curves and MIDI tempo based features like delay and envelope retrigger.
  • Four Multi-Envelopes, These free highly sophisticated envelopes can be built up using up to 32 sections. Full graphic control and additional menus with presets, load and save functions. Dynamic curves and MIDI tempo based functions.
  • Ten LFOs with various waveforms and are MIDI-syncable. Directly connected to main targets to make sound editing easy and fast. Directly connected LFOs for PWM A/B, Filter Frequency A/B, Tremolo (amp), Vibrato (main pitch) and Three Free LFOs. LFO have adjustable, free/poly/mono modes, keytracking, symmetry, smoothing, attack, decay and humanize functions.
  • Three modulation Step-sequencers with sequence loop start/end, poly/mono/free play modes, speed controls and step smooth function. Copy/paste/clear functions.
  • Modulation Matrix with 2 pages of 10 slots. 12 synth sources & 23 MIDI sources and 103 synth destinations.
  • 32 step mono sequencer, with sequencer length, speed adjust, slide amount, swing amount, volume smoothing. Each step has On/off, Reset, -32/+32 Semitune, Volume, Slide on/off, Filter A, Filter B and Free modulation settings. Clear, load and save functions to exchange sequences in between presets.
  • Poly/Mono/Legato/Seq synthesizer play modes. Portamento featuring legato, switch-able constant time/constant rate. Mono unison mode.
  • Adjustable Precision setting per oscillator to simulate the instability of vintage analogue synthesizers.
  • 16-voice polyphony. Voice amount control.
  • Global settings save with each individual preset like: keyboard velocity response curve, over-sampling settings and filter control smoothing.
  • Easy Edit page for fast new sound results or for easy access tempo changes.
  • External controller hardware (fader-box or synth) settings can be saved and restored.
  • Two effects-blocks with serial and parallel mode. Nine stereo effects available including Mono Delay, Stereo Delay, Chorus, Flanger, Phaser, Distortion, Low Fi, Stereo Widener and Reverb. MIDI tempo based settings in Delays, Phaser and Flanger.
  • Equalizer for total overall sound.
  • Sound banks of 32 presets inside built in browser. Preset handling with copy, paste, clear and compare function. Preset banks are sorted into style-maps for easy search.
  • All settings included the global settings are stored inside each individual preset.
  • Presets in clear categories by Rob Papen.
  • Arpeggiator: 32 step arpeggiator, with sequencer, seq length, speed adjust, slide amount, swing amount and step length control. Each step has On/off, Slide on/off, Reset, -32/+32 Semitone, Step length, Velocity, and Free modulation. Clear, load and save functions to exchange arpeggiators in between presets.

{See video at top of page}

User Reviews Average user rating of 5.00 from 3 reviews Add A Review

Blue II
Reviewed By FarleyCZ
February 24th, 2012

Version 2? Oh boy, it's good! FM8-like matrix is there! (Behaves a bit differently, but anyway!) All OSCs have all possibilities now as CPU power is higher nowadays. It has some nice samples in OSC's and it can use them to modulate or be modulated! Proper stereo unisono. More FX slots, more FXs. I can play with this thing for looong hours.


It's quite time ago when I've got copy of Blue from second hand. I didn't understand it back then, so I wasn't using it untill about four months ago. Then I rediscovered it and love it! :)

I want to start with a sound of it. At first sight it might seem a little bit "unstable", "not thick enough" and it's true for some uses. Imho It's not the best synth for subbasses for example. But when you dig in and use it's FM engine, you discover amazing sonic pallete. Someone somewhere called it cinematic. Can't agree more. It has some richness, something that just "tells the story" you play. It's especially handy when you have big track full of background layers and no freaking clue what to give on the top of it.

Another use is as really pleasant substitution for FM8. Especially now when Dubstep is wub-wub-wubbing everywhere, FM8 becme known again. Blue can do lot of similar sounds and it has it's own "extra" charater that diverse it from FM8 pretty well. Again, it just can tell the story. Emotionally. Can't describe it well. Just demo it. :) And as a bonus, it's sawtooth sounds much better then FM8's.

Handling of this synth is bit confusing at first, but when you get yourself around what FM is and how it works, it becomes pretty clean and quick. (Unless you're not preset hunter. Then it doesn't really matters...)

Featurewise also crazy. Not many synths alows you to tune precission of every single OSC's for example. :) Modulations are also great. Those multimode envelopes are really cool. ...and so on and so on. :)

Support is amazing. I've found a little bug it was performing with Ableton Live. Contacted guys, Jon opened those 6 years old codes and fixed it for me in literally no time. (2 days for bug fix like this is really a lightspeed) Bugfix was also included in next update.

Only bad thing is unisono engine that is oldfashioned and mono. But I've got a little "oficial-ish" roumor that version 2 is in planning, so no "dev-poke" point down thistime. :) (but it was close :p)

Summary? Well I believe it's one of most overlooked synths ever. It can really bring colours to your songs, which is amazing complment for all this "sometimes too clean" NI synth stuff everyone's using lately. Great sound, great possibilites, great FX, great developers and amazing potential to the future. Can't go otherwise than full score.

Read Review

Blue II
Reviewed By Feng
July 9th, 2007

Blue is an extremely versatile beast. It is able to produce an enormous sonic palette, and it's comfortable with all kind of sounds. Its main strength, in my opinion, is the extreme flexibility, due to infinite modulation possibilities, very flexible routing, the number of oscillators (six) and the waveforms to choose from (hundreds).
USER INTERFACE: Clear, logical, one can spend a lot of time programming without having eye stress.

SOUND: As I said, Blue can cover any sonic world with professional result.

FEATURES: That's where this synth really stands out. It has six oscillators that can be configured in a lot of ways. They can modulate each other with FM or sync(with various configurations possible), their output can be mixed as a normal analogue synth and any in between configuration is possible.There's also the possibility of waveshaping on any oscillator. Then the real strength is the modulation matrix, where you can almost freely set the modulator and the modulated parameter. There are step sequencers, multi point envelope, many lfos. Two filters are included. You can choose freely the routing. For example you can set two oscillators on filter A and other four on filter b. These filters are really responsive and sound good. An extensive effects section, with really good FX completes the picture. A fully customizable arpeggiator is included.

DOCUMENTATION: Although the synth interface is really clear, its enormous possibilities makes you want to have a look at the documentation which is clear and well written.

PRESETS: THey are from Rob Papen. Wonderful!

CUSTOMER SUPPORT: Incredible, Rob and Jon are making a perfect work. Any request is answered really soon.I had all my questions answered tipically within a few hours from posting them .

VALUE FOR MONEY: For 200 $ you have a powerful, wonderful synth. So again I have to give it the maximum.

STABILITY: Never had problems.

One more thing I want to underline is that BLUE has been considered a CPU hog. Obviously it depends on the complexity of the patch, but I find it in line with most of the modern beasts. WIth my athlon FX 4800 most of the patches take around 10% CPU. So it's not light on CPU, but it's definitely not a CPU HOG! What's more, you can reduce CPU by reducing oversampling!
Read Review

Blue II
Reviewed By Xiritam
July 7th, 2007

Kind of surprised that nobody reviewed this synth.
BLUE is a very very nice synth, it got nice filters, Sound is clear and clean and it became one of my go to synth if i want lush pads, warm squelchy basses and phat leads ( it really got a lot of good sounding pads basses and leads).
Its well worth the price, just like any other synths from Rob Papen and i recommend that you get this one.
One other thing i love about this synth is its interface.
Blue and White is a very good combination, makes you feel comfortable when you look at it.
About the sound engine, it got 6 OSC with tons of waveforms.
Filters are very nice sounding, having 13 types of filtering including VOX (love it),from 6 to 24db lowpass highpass bandpass notch, ring and comb.
This synth has a lot more features like the Step seq, Arp, FXs, Multi-Envelopes, fm routing, You just cant go wrong with this synth.


User interface - Very cool and clean interface, everything is organized, very userfriendly.Love the colors.

Sound - Breath taking Excellent professional Sound.

Features - A lot features. See above.

Documentation - it has manual anyways you might not need it.
This synth is very easy to use.

Presets - So many good sound presets. It got a lot of banks with tons of presets.

Customer Support - i dont know never had problems with it so i never had the need to ask for their help :p

Value for Money - Very worth it.

Stability - It never crashed my pc and it is very cpu Friendly. A bass presets takes about 2 % cpu load and pads 8 % ( using an amd athlon 3200+ single core cpu )
Read Review

Customers who like Blue II also viewed...

Products similar to Blue II...

More products by Rob Papen...

You viewed...