NPD User Guide


NPD is an intuitive phase distortion synthesiser with a streamlined interface. It works as an Audio Unit extension (AUv3) inside host applications such as GarageBand, Cubasis, Auria Pro, modstep and AUM.

User Interface

NPD interface consists of 2 views of controls titled Main and Modulation & FX. The Main view consists of the oscillators, filters, envelopes and LFOs. The Modulation & FX consists of the Modulation Matrix, FX and the output section.

Parameter Controls

  • Knob: Touch and drag your finger vertically to adjust the value.
  • Number Box: Touch and drag your finger vertically to adjust the value.
  • Pop-up menu: Tap and choose an item from the popover.
  • XY Pad: This control allows you to control 2 parameters at the same time. Drag the main puck to adjust both X and Y parameter values simultaneously. To control them independently use the dedicated handles.
  • Envelope: Envelope segment level, time and curve values can be adjusted independently with the dedicated handles. Level and curve values are adjusted by dragging corresponding handles vertically. Time values are adjusted by dragging the handles horizontally.
  • On/off switch: Tap the switch to toggle it.

Parameter Values and Numeric Pad

When adjusting a parameter the title of its control is replaced by the parameter value. In order to view the parameter value without adjusting it simply tap on its control or handle. The values can be set precisely using the built-in Numeric Pad. Simply tap on the value and the Numeric Pad will be presented. Number Box requires a double tap to get to the Numeric Pad.

Preset Selector

  • Preset Selector is always displaying the currently selected preset.
  • Tap it to browse and select presets from the popover.
  • From the popover you can swipe the preset name to the left and you will be presented with options to rename or to delete the preset. Swiping right gives you an option to export the preset. Note that these only work for the user presets.
  • Tap the previous or next button to switch between presets.
  • Tap the Save button to save the current synth state as a new preset.
  • You can drag and drop previously exported NPD presets onto the interface from another app (e.g. Files app) to import presets.


NPD comes with 3 phase distortion oscillators (Osc 1, Osc 2 and Sub) and one noise oscillator.

  • Shape: Shape of the waveform. At 0% it has a square wave shape while at 100% it's closer to sawtooth.
  • Harmonics: Harmonic richness of the sound. Modulating it sounds similar to filter sweeps.
  • Pan: Pans the oscillator.
  • Level: The oscillator output level.


NPD comes with 2 resonant filters.

  • Type: Filter type.

Filters Routing

Filter Routing lets you choose various routing options.

  • Serial: Routes all oscillators into Filter 1 and then the output signal is routed into Filter 2.
  • Parallel: Routes all oscillators into both Filter 1 and Filter 2 and halves the summed signal.
  • Split: Routes Oscillator 1 into Filter 1, Oscillator 2 into Filter 2 and half of Sub-oscillator and Noise signals are sent to both filters.
  • F2: Noise Only: Routes Oscillator 1, Oscillator 2 and Sub-oscillator into Filter 1 and Noise into Filter 2.


NPD comes with 3 envelopes (Amp, Env 2 and Env 3). They can all be used as modulation sources. The Amp envelope is hard wired to control all oscillator levels. Envelopes are highly flexible and all segments have adjustable time, level and slope parameters. The Amp envelope's Level 3 parameter is locked to 0% for obvious reasons.

  • Mode: In Sustain mode, the envelope gets to and stays on sustain level until the key is released. In Trigger mode, envelope doesn't stop on sustain and decays straight away. This is useful for drums and the other one-shot sounds. In Loop mode, envelope doesn't stop on sustain level or the final level, it loops back to the start of the envelope and keeps repeating this until the key is released.
  • Biased: When this option is on, the sustain level has the value 0. Levels below sustain are negative and above are positive. This is analogues to the LFO Bipolar parameter. Note that, this option is ignored by the level targets (oscillator Level and the master Output parameters).


  • Waveform: LFO shape. There are 6 shapes to choose from.
  • Rate: LFO rate which can be tempo synced.
  • Depth: LFO depth.
  • Left/Right Phase: Left and right channel phase offset.
  • Sync: Toggles host tempo synchronisation.
  • Bipolar: When it's on the waveform values are in [-0.5, +0.5] range instead of [0.0, 1.0] range. Note that, this option is ignored by the level targets (oscillator Level and the master Output parameters).
  • Retrig: When it's on each note triggers its own LFO.

Modulation Matrix

Modulation Matrix allows you to modulate almost any parameter of NPD with the common MIDI sources as well as Envelopes and LFOs. The synth has 16 modulation slots. Use the Default preset as a starting point, which has common parameters already hooked up. For a clean slate start from the Init preset.

For the level targets (oscillator Level and the master Output parameters), the total modulation amount is a product of all source signals. For all the other targets, the total modulation amount is a sum of all source signals.

  • Source: Modulation source.
  • Intensity: Modulation intensity.
  • Target: Modulation target.


  • Bypass: Bypasses the effect.
  • Tone: Distortion tonal quality (LP filter).
  • Drive: The additional gain applied to the input signal.
  • Output: Output gain.
  • Mix: The effect dry/wet mix.


  • Bypass: Bypasses the effect.
  • Rate: The frequency of the LFO.
  • Feedback: The amount of effect signal routed back to the input.
  • Spread: Stereo spread of the effect.
  • Mix: The effect dry/wet mix.


  • Bypass: Bypasses the effect.
  • Rate 1: The frequency of the LFO 1.
  • Rate 2: The frequency of the LFO 2.
  • Intensity: Intensity of the chorus effect.
  • Mix: The effect dry/wet mix.


  • Bypass: Bypasses the effect.
  • Time: Delay time.
  • Feedback: The amount of effect signal routed back to the input.
  • Filter: LP filter cutoff for the delayed signal.
  • Feedback Mode: Delay has four feedback modes. Cross feedback sends the left channel output to the right channel and vice versa. In inverted feedback mode, both channel signals are inverted before they are fed back.
  • Smoothing: Time it takes for the effect to transition to the new delay time after the Time parameter is changed to a new value.
  • Mix: The effect dry/wet mix.


  • Output: Master output level of the synth.
  • Voices: Voice mode can be set to Mono, Legato or a number of polyphonic voices. Keep polyphonic voice count low to save on the CPU resources.
  • Glide: The time it takes to glide from one note pitch to another.

CPU Performance

  • Each voice has its own FX units. This allows FX parameters to be targets in the modulation matrix. Hence, more voices you have enabled more CPU resources it will need. Decrease the number of polyphonic voices if not needed or bypass FX units that you don't need to run the synth more efficiently.