Pulsor Suite by Amazing Noises

Pulsor 2 has 4 oscillators; each oscillator has its own waveform and modulation/distortion algorithm.
All the oscillators have two buttons:

• Freq/Pitch Button to change between Frequency and Semitone values
• Fix/Rel Button to change between fixed frequency/pitch and MIDI relative frequency/pitch.

In Pitch mode the dial is incremented in cents (1/100 of semitone) when dragged with the mouse. If you want a larger increment press the Command (Mac) or Control (Windows) key when dragging.

When in Rel(ative) mode, the frequencies are referred to the note C3: so, for instance if you set a frequency of 100 Hz for an oscillator, it will be 100 Hz when you play a C3 MIDI note, but it will be a 200 Hz frequency if you play a C4 MIDI note. If you always want the same frequency for all notes, switch to Fix(ed) mode.

There are two modulation sources for the oscillators: the Multi Modulators (more later) to modulate the amplitude and the LFO/Envelopes (more later) to modulate the timbre/distorsion parameter.

MIX SECTION

There are 3 dials, from the upper left we will call them Mix 1, Mix 2 and Mix 3: the two dials inside the rectangular frame (Mix 1 and Mix 2) are used to mix Oscillators 1 and 2. The dial below the rectangular frame (Mix 3) is used to mix the previously mixed couples of oscillators 1/2 and 3/4.
Note that to the left of Mix 1 there is a RingMod parameter: this is an additional mixing stage between a ringmodulation of oscillator 1 and 2 and Mix 1. In other words, when the RIngMod parameter is 0%, only M
As you can see Mix 1 signal is routed to Mix 3, which also receives a signal from the oscillators 3 and 4 frame. With these two dials you can carefully blend the sound of each oscillator.
Note that to the left of Mix 1 there is a RingMod parameter: this is an additional mixing stage between a ring modulation of oscillator 1 and 2 and Mix 1. In other words, when the RIngMod parameter is 0%, only Mix 1 is sent to Mix 3, when theRIngMod parameter is 100%, only the ring modulation is sent to Mix 3. Other values give a different mixing of the ring modulation and Mix 1.

Mix 2 signal is used to modulate the frequency of Oscillator 4 (see above): mixing the two possibly distorted waveforms of the first two oscillators you can create some complex frequency modulations. If you consider that you can modulate the amplitude of the two oscillators with the Multi Modulators and change the amount of distortion/modulation with the LFO/Envelopes, the possibilities are endless. And (if this is not enough) each Mix dial can be modulated by the LFO/Envelopes!

The global signal Mix 3 is sent to a Multi Modulator for further amplitude modulation and then to a Filter Distortion section.

FILTER DISTORTION

In this section the signal is first distorted using an algorithm not used in the oscillators distortion (parameter Distort), then sent to a 24 dB “analog-morphing” filter (the filter is different from the one in Pulsor 1, it is a zero-delay feedback nonlinear SVF). Note that the Distortion parameter can be modulated by theLFO/Envelopes modulators.

The filter has a parameter, lbh, to morph its charachteristics from low-pass (value 0), band-pass (value 0.5) and high-pass (value 1).
The Cut Freq parameter is relative to the MIDI note played and can be modulated by the LFO/Envelopes modulators.

The Sens(itivity) parameter is used to further modulate the cut off frequency by means of the Amplitude Envelope (see below) or of a Multi Modulator.

Below the Distortion Filter frame there is a DryWet parameter to mix the unfilterd and filtered signals.

OUTPUT

After the filtering the signal is shaped by an Amplitude Envelope (the frame on the right) wich has an Exp parameter (to get exponential segments) and a VelSens(Velocity Sensitivity) parameter expressed in dB.

Before been sent out the signal spectrum can be “stretched” using the Stretch andStr Div parameters. The Stretch parameter is a multiplication factor of the distance between the harmonics of the oscillators. For instance, if the oscillator fundamental is 100 Hz, and the Stretch factor is 3, the spectrum would be 100, 400, 700, 1000 Hz and so on. The Str Div parameter is a division factor: for instance, if the oscillator fundamental is 100 Hz, and the Str Div factor is 3, the spectrum would be 100, 133.3, 166.6, 200 Hz and so on. You can set both parameters and have a stretching factor, for instance, of 5/4 (Stretch: 5 and Str Div: 4). Nota that the stretching factor is calculated on the MIDI note you send to the synth: so if the actual frequency of the signal doesn’t correspond to that of the MIDI note, the result could be unpredictable (and this is not a bad thing!).

The signal is then rescaled by the Gain parameter on the left.

There are two Multi Modulators, which are a series of different unipolar (i.e. only positive) oscillators with parameters to change their shape.
The waveforms for each modulator (selectable with the top menu) are:

Depending on the waveform there are these additional parameters:

• Offset (a sort of exponential DC offset: try it to see how it works) Exp (exponential shaping: again, try it to see how it works)
• Duty (duty factor for pulse waveform)
• Slide (this parameter smooths the pulse edges)
• Trisaw (for triangle waveform only, morph between sawtooth and triangle shape).

The Div and Var parameters (on the right of the Multi Modulator frame) are used for a stuttering effect: f.i. a Var of 3 means that the waveform cycle is divided into 3 faster cycles. The Var parameter sets a random variation of the subdivision: f.i. withDiv = 5 and Var = 2 the possible subdivisions are 3, 4, 5, 6 and 7 (two slower than 5 and two faster). The Prob parameter below sets the probability that the stutter actually occur. The Stop parameter sets the probabilty that the modulator stops for a cycle.

Between the two Multi Modulators there is a Mix dial to mix the signal of the modulators: note that this parameter can be modulated by the LFO/Envelopesmodulators.

Moreover the two modulators are multiplied, so we have 4 sources of modulation:Mod 1, Mod 2, Mult and Mix.

LFO/ENVELOPES MODULATORS

These modulators are on the top of the Floating Panel: there are 2 LFOs and 2 Envelopes.

The LFO parameters are Frequency, Random factor and Modulation Depth.
There are actually two LFO modes

• “normal” mode: the Random factor represents a frequency deviation of the sine wave LFO.
• “interpolate” mode: the Random factor represents an interpolation between a sine wave and a random wave.

The Envelope parameters are Attack and Release times, Curve (exponential) factor, Depth and Legato/Retrigger switch.

To see how they work let’s take a look at one of the many LFO/Envelopes chooserswe find in the Oscillators parameters. The list of items is the following:

• no (no modulation)
• m1+ (first LFO in normal mode)
• m1- (reversed first LFO in normal mode) m1i (first LFO in interpolate mode)
• m2+, m2-, m2i (see above)
• e1+ (first envelope)
• e1- (first envelope reversed)
• e2+, e2- (see above)

The Depth factor for the LFOs depends on the nearest limit of the modulated parameter.
F.i. if the modulated parameter range is 0-10, and the actual, unmodulated, value is 8, the maximum possible depth is 2, so the value can oscillate between 6 (i.e 8-2) and 10 (i.e. 8+2). In this case if the Depth is 100% (the maximum) the value oscillates between 6 and 10, if it is 50% it oscillates between 7 and 9 and so on.

For the Envelopes the Depth parameter is always related to the lowest limit. So if the value is 8 and the depth is 100% the envelope goes from 0 to 8, if the depth is 50% the envelope goes from 4 to 8 and so on. The reversed envelope goes from 8 to 0, from 8 to 4 and so on.