Introduction to BLUE

BLUE is a cross-fusion virtual synthesis synthesizer with 16 note polyphony, including some extraordinary new ideas and features. The synthesizer is designed so that it makes use of subtractive, FM, PD and WS synthesis methods. To make it easy to use and understand it follows the classic subtractive synthesis audio route and control.

Audio signal flow

The block diagram below shows the audio signal flow within BLUE. The five Amp-modules, shown below, are not visible in the user screen of BLUE, but are centrally controlled by the Volume Envelope, which you can find in the LCD screen section. The six oscillators inside BLUE have several audio routes; these routes depend on the chosen algorithm.


GUI design / user interface

The GUI design of BLUE can be divided into three main sections: Oscillator, Filter and LCD screen. Below these section is the central volume control and the parameter readout field.


At the oscillator section many parameters can be found for fast access. Also the filter section has a comfortable layout with knobs for main functions.

The LCD screen offers multiple synthesizer sections. From the Preset page, Easy edit page to the Algorithm selection, the main envelopes, modulation tools, Sequencer, the FX section and the Global page. Below the LCD screen, you will find the parameters readout; this shows the value of current control, which is very handy and precise. Also the selected preset is displayed in the preset display.

Cross-fusion synthesis

To understand cross-fusion synthesis look at this picture below. You can see that at the right-hand side are shown the most important sections of the LCD screen. The first one is the "Algo" section this you determines which algorithm the oscillators uses. The oscillators can be modulate by another oscillator, either using FM or Ring Modulation, by having an input from another oscillator. For FM synthesis or Ring modulation sounds an Envelope is needed to control the volume of each oscillator however, if you keep the volume at full the oscillator behaves as subtractive synthesis oscillator, it's up to you to decide if you want an oscillator with envelope volume control or without.

Next you can send the oscillators that are output (depending on the algorithm) into either Filter A, Filter B or both. Both have their own envelopes. The last stage before going into the FX section or Dry output is the Volume Envelope, this alters the volume of the whole of the sound.


Of course there are many other features that are inside the LCD screen, like LFOs, step sequencers... and so on.

As was said before, BLUE follows the basic subtractive signal route. Therefore all major Envelopes are set together, this is shown in the displayed below. The Volume envelope always has global control of the volume. Above it you can see the Filter envelopes (if you use the filters) and above them Oscillator envelopes.


One example of how flexible BLUE is, is preset "Conviction". You can find this preset in bank "01_Diverse 02".

  • Osc A goes into Filter A and is not controlled by a volume envelope
  • (Osc A Envelope amount is zero)
  • Osc C and D FM modulate Osc F and each uses its own oscillator volume envelope.
  • Osc F which is modulated by Osc C & D, has no volume envelope, so the global volume is set by the main volume envelope

BLUE offers you allot of interesting combinations. You can combine FM type sounds with classic subtractive synthesis and on top of that also phase distortion and wave shaping...

Hopefully, this chapter has given you a brief overview of how BLUE works. More detailed information can be found in the following chapters.

Index