version 0.5, work in progress..

Before you begin

One of the biggest advantages of Sunrizer synth is the Morph Group function. It lets you store two different configurations of knobs and faders (including DSP effects) in a single preset and continuously morph between these parameters during playing, using only the modulation wheel. All knobs and faders settings can be stored in two different states – A and B. You can immediately switch between these states with buttons A and B located above the modwheel. The currently displayed state is indicated by diodes located on A or B button.

A good practice: Before you start editing parameters make sure the modulation wheel is at minimum (A) position.

Parameters automation works only for state A

If you are familiar with subtractive synths

This picture explains some less usual elements


An oscillator is a basic source of sound in every analog synthesizer. Sunrizer uses a pair of these (OSC1 and OSC2) which can work independently or in synchronized mode.

When you hit a key on a piano keyboard, both oscillators will start to generate continuous waveforms.

There are four different types of waveforms that can be selected with a button.

Saw, square and triangle are basic waveforms, typical for classic analogue synthesizers. First one has a bright, buzzy character that is great for basses, pads and leads.

Square waveform has more hollow character that evokes both pads and old school video games. Triangle is a light and calm waveform, perfect for creating soft and woodwind instruments.

SuperSaw is different. It sounds like seven saw oscillators playing together slightly detuned and is very effective in making trance pads and other modern rich voices.

Two knobs located in both oscillator sections allow you to alternate the shape of waveform. When SuperSaw is selected Width/Sub knob controls the depth of detune, Mix/PWM knob controls the volume level of detuned sound.

When saw, square or triangle is selected, Width/Sub knob lets you to mix additional sub oscillator sound which plays tones one octave lower. Notice that unlike in a classic analog synthesizer, sub oscillator has the same waveform as main oscillator.

For square waveform you can optionally change the pulse width value using Mix/PWM knob.

OSC2 section has also three parameters that allow to transpose the notes played by the second oscillator.

Semi knob lets to transpose a tone up and down by 12 semitones

Cents knob lets to transpose up and down, more precisely, to 1 semitone.

Octave button located on the left allows to transpose a tone up by 1 or 2 octave.

To achieve additional interesting sound on oscillator 2, you can synchronize its work with oscillator 1. So called “Hard sync” is often known from vintage analog synthesizer. The effect ensures that both oscillators are technically playing at the same frequency, but the irregular cycle of the second oscillator causes unnatural timbres and higher amount of many frequencies. Press the SYNC button and try to detune oscillator 2 using SEMI knob or automatically modulate its pitch with LFO. The “Hard sync” works only if oscillator 2 is generating saw or square waveform.

There is an additional O->FLT2 button in the section. This one make it possible to route the signal from oscillator 1 strictly to filter 1 and from oscillator 2 to filter 2 only.

Multi section

On the left side of oscillators section you can find the “Multi” bar. When multi mode is turned on for a specific oscillator (buttons: osc1 , osc2) oscillator acts like 3 detuned oscillators. Detune knob controls detuning in a very small range – this may be used to achieve Unison effect – the sound gets “fatter”. With Spread knob you can move apart the partial oscillators up to 12 semitones – to create chords, atonal sounds or more expressive patch. The Side/O knob controls mix volume of partial oscillators and main (middle) oscillator. In FM mode the bottom oscillators frequencies are modulated by the sum of upper oscillators. ( O1A + O1B + O1C make the modulation signal ).

You should realize that, when the multi mode is turned on for both oscillators, a single voice consists of 2 oscillators * 2 sub-oscillators * 3 multis = 12 oscillators! (with full polyphony). This number grows up to 28 saw oscillators when super-saw wave is used.


In this section sounds generated by both oscillators are being mixed together. You can modify the mixer settings by turning three knobs : O1/O2 sets the proportion between volume level of signals from oscillators 1 and 2.

R-Mod set the depth of ring-modulation, an old-school electronic effect that multiplies signals to produce rich in high frequencies, bell-like or otherwise metallic sounds. This effect becomes noticeable when signal from oscillator 2 is audible and slightly detuned.

O/Noise sets the proportion between volume level of oscillators signal and noise generator.

Color sets so called noise color - between low and high passed


This section consist of two independent filters and ADSR envelope that brings additional control over filter settings. Audio filter is an effect which modifies the audible spectrum of a signal. In other words a filter can be used to remove certain audio bands from the original signal. When it comes to synthesizers this effect is essential for shaping sounds.

The filters may work in two different modes which can be set using the ROUTE button.

In serial mode (1->2) signal from the mixer is routed to the first filter and next into second one.
In parallel mode sound from the mixer is being converted into two identical signals and both go through different filters independently.

You can choose between various filter types from the list. Simply tap one of the dark blue displays and pick a filter from the list.

  • LP (Lowpass) filter passes low frequency signals and attenuates frequencies higher than a certain value (called cutoff).
  • Power LP signal is distorted and then filtered by LP filter.
  • HP (Hipass) filter passes high frequencies and attenuates signals below a certain value.
  • BP (Bandpass) is more complex and passes frequencies within a certain range and rejects frequencies outside that range.
  • NOTCH is a filter that passes most frequencies unaltered, but attenuates those in a specific range to very low levels.
  • COMB filter adds a delayed version of a signal to itself, causing constructive and destructive interference . The frequency response of a comb filter consists of a series of regularly spaced spikes, giving the appearance of a comb.
  • FORMANT filter adds character to sounds in the way a vocal tract or an instrument body does.
  • ALLPASS filter is the one that passes all frequencies equally, but changes the phase relationship between various frequencies.
  • RESAMPLER changes sample rate of incoming signal
  • RESONATOR filter adds resonant peak to the input signal

If set to BYPASS, the filter will not affect the sound at all.

LP, HP and BP are able to work as 12dB or 24dB filters. Switch between them by pressing the 24dB button.

The Env-Amt (Envelope amount) knobs determine how much the filter ADSR envelope affects the current settings of cutoff parameters.

When the TRACK button is on , the cutoff frequency setting will be higher for higher notes you play. When it is off the cutoff frequency will be constant.


The Amp fader determines the overall volume level of current preset.

The ADSR (Attack, Decay, Sustain, Release) envelope controls the volume of a single note that changes over time from a moment when the key has been pressed or note started by the arpeggiator/sequencer.

The contour of an ADSR envelope is defined by four parameters, set with four faders.
Attack - specifies the time it should take for the envelope to reach maximum level after you
have pressed a key.
Decay - sets the time the volume level goes down after the attack phase is over.
Sustain -sets the target volume level the envelope reaches in the decay phase.
Release - specifies how long it should take for the envelope to decay from the sustained level.
Try playing around with the ADSR knobs, see what a long attack does, short decay with small sustain or long release.


There is a separate section of the synthesizer that allows to automatically modulate various sound parameters previously discussed.

For example, it can continuously change the value of a filter cutoff setting, pitch or volume level. LFO (low frequency oscillator) can produce non-audible waveforms with very low frequencies (0 – 20hz) which be send to almost any sound parameter you like.

Sunrizer offers two independent LFOs per voice, both running in 3 modes (trigger, 1 shot or global), generating one of 6 different waveforms (sinus, square, random, exponential, triangleor continuous random).

Tap the small dark blue display to choose from the parameters that can be modulated. To switch between settings for LFO 1 and 2 simply press the LFO button.

FREQ knob sets the LFO's speed.
AMOUNT determines how much the LFO signal affects selected destination parameter.
PHASE allows you to set the staring point of the generated waveform.
FADE IN specifies the time it should take for the Amount to reach maximum level after you have pressed a key. (This works only in Trigger and 1 Shot modes. )

In Trigger mode the LFO cycle will be restarted each time you play a new note. If you switch to 1 Shot mode, LFO will generate only one cycle each time you play a new note. Choose Global mode if you do not want the LFO to be restarted at all. This particular mode

is very useful for pad-like sounds where filter cutoff is going up and down in very long cycles. Look into LFO 1 settings for preset 'Amplified Universe' and hear how the filters work when LFO is set to global mode. Optionally you can synchronize the frequency of your LFO unit with internal or arpeggiator 's tempo by pressing the SYNC button.


When it comes to sequencing sounds, Sunrizer incorporates very powerful programmable arpeggiator. Think of it more like of a small step sequencer.

The editor allows to create patterns of single notes and chords with more than 256 steps per sequence. You can select one of many ready-made patterns or create and save your own. To switch the synth to arpeggiator mode, use the MODE button.

Add, copy and delete steps by pointing them with your finger and taping +, +c and – symbols.

In each step of the sequence you can specify how many notes should be played together by setting the voices parameter and how to transpose these notes up or down.

The set of Action – finger commands can tell the arpeggiator which of the notes pressed on the keyboard must be considered as first note tobe played in the current step. Furthermore, there are two special attributes that can be assigned to each step. Hold makes the sequencer play notes longer than during one step.
Glide creates glissando effect, which makes a pitch of previous note to change smoothly to another.

Tutorial on Sunrizer arpeggiator by iOS Music and You