Parameter Reference

Here, we provide details of parameters that can be set for each of the generators via the preset .yml files or using the modify_preset() Generator method.

A subset of these parameters are also 'mappable', i.e. can be controlled by input data via the Sources:

polar
azimuth
theta
volume
pitch
cutoff
spectrum
pitch_shift
volume_envelope/A
volume_envelope/D
volume_envelope/S
volume_envelope/R
volume_lfo/freq
volume_lfo/freq_shift
volume_lfo/amount
pitch_lfo/freq
pitch_lfo/freq_shift
pitch_lfo/amount

While a further subset of these are also 'evolvable', i.e. can be evolved over time using an Object-type source:

polar
azimuth
theta
volume
cutoff
pitch_shift
volume_lfo/freq_shift
volume_lfo/amount
pitch_lfo/freq_shift
pitch_lfo/amount

When mapping data input into Sources to expressive sound parameters, two numerical ranges are relevant - the mapping limits of the input parameters, and the range of values the mapped parameter can assume - the map_lims and param_lims arguments of the Sources modify_preset() Sources method, respectively.

The mapping limits, map_lims, are the minimum and maximum allowed values of the input data. Data values above or below the range are clipped to the corresponding limits. These can either be absolute values, specified numerically (e.g. 1.0) or percentiles, specified as a string (e.g. '100'). The param_lims then define the minimum and maximum values of the chosen sound parameters that the data are rescaled between. For example if map_lims={'pitch_shift', [0,3]} and param_lims={'pitch_shift', [0,24]}, data values of 1.25, 2 and 3 mapped to pitch_shift will result in pitch shifts of 10, 16 and 24 semitones, respectively.

Sampler Generator

The Sampler generator type can be used to modify and play audio samples (sound recordings) .

Parameter	Description	Default Value	Default Range	Unit
name	Preset name	default	-	-
description	Full description of the parameters selected for this preset, e.g. looping, volume and pitch envelopes, filters, etc.	Default preset for the sampler, basic setup with no looping, and an on-off volume envelope.	-	-
note_length	Numerical note length in seconds, or 'sample' for the sample length, or 'none' to last to the end of the sonification.	sample	['1e‑2'‑30.0]	seconds
looping	Option to play the sample on a loop. 'off' for no looping 'forward' to loop forwards, 'forwardback' to play the loop back and forth	off	-	-
loop_start	If looping, starting point of loop in seconds.	0.0	-	unitless
loop_end	If looping, ending point of loop in seconds. If loop_end is longer than the sample, clip to end of the sample.	10.0	-	unitless
filter	Apply a frequency filter to to the audio signal. Values are ‘on’ or ‘off’. A filter affects the timbre by filtering out certain harmonics	off	-	-
filter_type	Low pass filter (only allows frequencies lower than your cutoff to pass through) High pass filter (only allows frequencies higher than your cutoff to pass through)	LPF1	-	-
cutoff	The cutoff frequency (or 'knee') of the filter, beyond which frequencies are attenuated. as a fraction of the maximum frequency	1.0	[0.0‑1.0]	fraction
volume	Master Volume of generator.	1.0	[0‑1.0]	fraction
pitch	Default pitch selection (used by all generators)	1.0	[0‑1.0]	unitless
azimuth	Azimuth coordinate for spatialising audio into differing channels	0.0	[0.0‑1.0]	cycles
polar	Polar coordinate for spatialising audio into differing channels	0	[0.0‑1.0]	half-cycles
pitch_hi	Pitch range maximum in semitones	36	-	unitless
pitch_lo	Pitch range minimum in semitones	0	-	unitless
pitch_shift	Default shift in semitones	0.0	[0.0‑24.0]	semitones

volume_envelope parameter group

Define the note volume envelope applied to the samples. ‘ADSR’ is a common parametrisation in sound synthesis, find out more e.g. at this link.

Parameter	Description	Default Value	Default Range	Unit
A	Attack, how long it takes for a sound to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the sounds volume to die down to the Sustain value after the Attack period.	0.0	['1e‑2'‑20.0]	seconds
S	Sustain, the volume level (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long the tone takes to finally die away once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total amplitude level of the envelope from 0 to 1, contolling maximum volume of the note.	1.0	[0.0‑1.0]	fraction

pitch_lfo parameter group

Controls for the 'Low Frequency Oscillator' (LFO) used to modulate pitch of notes at rhythmic frequencies. In music this is often referred to as 'vibrato'.

Parameter	Description	Default Value	Default Range	Unit
use	Switch feature on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	saw	-	-
amount	the amplitude of the maximal pitch oscillation from the underlying pitch	0.5	[0‑2]	semitones
freq	Base frequency of the LFO oscillations.	4	[1.0‑12.0]	Hz
freq_shift	Shift relative to the base LFO frequency.	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.3	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction

volume_lfo parameter group

Controls for the 'Low Frequency Oscillator' (LFO) used to modulate volume of notes at rhythmic frequencies. In music this is often referred to as 'tremolo'.

Parameter	Description	Default Value	Default Range	Unit
use	switch volume LFO effects on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	sine	-	-
amount	The amplitude of the maximal volume oscillation from the underlying pitch	0.5	[0‑1]	unitless
freq	Base frequency of the LFO oscillations.	2	[1.0‑12.0]	Hz
freq_shift	Shift relative to the base LFO frequency	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle.	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.3	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction

---

Synthesiser Generator

The Synth generator type can be used to synthesise sound using mathematically generated waveforms or oscillators. The preset can be used to modify the relative frequency, phase and amplitude of these oscillators.

Parameter	Description	Default Value	Default Range	Unit
name	Name of the preset	default	-	-
description	Full description of the preset purpose and parameters.	Default preset for the synthesizer, using three saw wave oscillators, two of which are detuned slightly higher and lower respectively, with lower volumes. This gives a harmonically rich sound, suitable for filtering, with detuned unison saws removing some harshness.	-	-
note_length	Numerical note length in seconds	0.1	['1e‑2'‑30.0]	seconds
filter	Do we apply a frequency filter to the audio signal? This can be used to change the balance of frequencies and manipulate the ‘timbre’ of a note	off	-	-
filter_type	Choose from available filter types	LPF1	-	-
cutoff	The cut-off frequency (or knee) of the filter, beyond which frequencies are attenuated. Specified between 0 and 1 as a fraction of the audible range of notes we can hear (E0 to D#10).	1.0	[0.0‑1.0]	fraction
volume	Master Volume of synthesizer	1.0	[0‑1.0]	fraction
pitch	Default pitch selection	1.0	[0‑1.0]	unitless
azimuth	Azimuth coordinate for spatialising audio into differing channels	0.0	[0.0‑1.0]	cycles
polar	Polar coordinate for spatialising audio into differing channels	0	[0.0‑1.0]	half-cycles
pitch_hi	Pitch range maximum in semitones	0.1	-	unitless
pitch_lo	Pitch range minimum in semitones	0	-	unitless
pitch_shift	Default shift in semitones	0.0	[0.0‑24.0]	semitones

oscillators parameter group

Oscillator information. Oscillator are denoted osc<n>, allowing an arbitrary number of oscillators to be combined to make the intrtinsic tone. The default preset demontrates this using 3 sawtooth oscillators, slightly detuned from each other to create a ‘detuned saw’ sound, hence the identically structured oscillators below.

osc1 parameter group

Parameter	Description	Default Value	Default Range	Unit
form	Type of waveform used for oscillator 1, choose from [‘saw’, ‘square’, ‘sine’, ‘tri’, ‘noise’]	saw	-	-
level	Amplitude of the oscillator from 0 to 1, contolling maximum volume of the note	1.0	-	unitless
detune	Change in tuning as a percentage of the input frequency	0.0	-	unitless
phase	The phase of the oscillator, defined in terms of fraction of a whole cycle	0	-	unitless

osc2 parameter group

Parameter	Description	Default Value	Default Range	Unit
form	Type of waveform used for oscillator 2, choose from [‘saw’, ‘square’, ‘sine’, ‘tri’, ‘noise’]	saw	-	-
level	Amplitude of the oscillator from 0 to 1, contolling maximum volume of the note	0.5	-	unitless
detune	Change in tuning as a percentage of the input frequency	0.75	-	unitless
phase	The phase of the oscillator, defined in terms of fraction of a whole cycle	0.3	-	unitless

osc3 parameter group

Parameter	Description	Default Value	Default Range	Unit
form	Type of waveform used for oscillator 3, choose from [‘saw’, ‘square’, ‘sine’, ‘tri’, ‘noise’]	saw	-	-
level	Amplitude of the oscillator from 0 to 1, contolling maximum volume of the note	0.5	-	unitless
detune	Change in tuning as a percentage of the input frequency	0.75	-	unitless
phase	The phase of the oscillator, defined in terms of fraction of a whole cycle	0.6	-	unitless

volume_envelope parameter group

Define the note volume envelope applied to the samples. ‘ADSR’ is a common parametrisation in sound synthesis, find out more e.g. at this link

Parameter	Description	Default Value	Default Range	Unit
A	Attack, how long it takes for a sound to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the sounds volume to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the volume level (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long the tone takes to finally die away once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1.0	[0.0‑1.0]	fraction

pitch_lfo parameter group

Controls for the ‘Low Frequency Oscillator’ (LFO) used to modulate pitch of notes at rhythmic frequencies. In music this is often referred to as ‘vibrato’

Parameter	Description	Default Value	Default Range	Unit
use	Switch pitch LFO effects on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	sine	-	-
amount	The amplitude of the maximal pitch oscillation from the underlying pitch	0.5	[0‑2]	semitones
freq	Base frequency of the LFO oscillations.	3	[1.0‑12.0]	Hz
freq_shift	Shift relative to the bae LFO frequency	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	“Curvature” of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	“Curvature” of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	“Curvature” of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total amplitude level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction

volume_lfo parameter group

Controls for the ‘Low Frequency Oscillator’ (LFO) used to modulate volume of notes at rhythmic frequencies. In music this is often referred to as ‘tremolo’.

Parameter	Description	Default Value	Default Range	Unit
use	Switch pitch LFO effects on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	sine	-	-
amount	the amplitude of the maximal volume oscillation from the underlying pitch	0.5	[0‑1]	unitless
freq	Base frequency of the LFO oscillations.	3	[1.0‑12.0]	Hz
freq_shift	shift relative to the bae LFO frequency	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	“Curvature” of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	“Curvature” of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	“Curvature” of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction

---

Spectraliser Generator

The Spectraliser generator type can be used to represent a frequency spectrum, by mapping any frequency range to an audible range, and generating a representative sound signal (using an IFFT approach). In this approach, narrow spikes become tones at their frequency position, a sloped continuum becomes coloured noise, etc. Note: this generator must take a spectrum input, as an array, representing ‘flux’ or ‘power’ values of a spectrum, arranged from lowest to highest frequncy.

Parameter	Description	Default Value	Default Range	Unit
name	name for a particular preset.	default	-	-
description	full description of what a preset does.	Default preset for the synthesizer, using three saw wave oscillators, two of which are detuned slightly higher and lower respectively, with lower volumes. This gives a harmonically rich sound, suitable for filtering, with detuned unison saws removing some harshness.	-	-
note_length	Numerical note length	0.1	['1e‑2'‑30.0]	seconds
filter	Do we apply a frequency filter to the audio signal? This can be used to change the balance of frequencies and manipulate the ‘timbre’ of a note	off	off	-
filter_type	Choose from available filter types	LPF1	LPF1	-
cutoff	The cut-off frequency (or ‘knee’) of the filter, at which frequencies are attenuated beyond. specified between 0 and 1 as a fraction of the audible range of notes we can hear (E0 to D#10).	1.0	1.0	fraction
volume	Master Volume of generator	1.0	[0.0‑1.0]	fraction
interpolation_type	How to interpolate and resample points in the spectrum. “sample”: interpolate spectrum values directly; “preserve_power”: integrate, interpolate then differentiate to avoid missing power in narrow features.	sample	-	-
regen_phases	Boolean, for an evolving spectrum, do we regenerate phases for each buffer, or keep the same?	True	-	-
fit_spec_multiples	Boolean, whether or not to generate IFFT such that the spectrum sample points are hit exactly.	True	-	-
min_freq	Minimum sound frequency used to represent the data	50.0	[20‑'2.2e4']	Hz
max_freq	Maximum sound frequency used to represent the data	2000.0	[20‑'2.2e4']	Hz
pitch	Default pitch selection (used by all generators)	1.0	[0‑1.0]	unitless
azimuth	Azimuth coordinate for spatialising audio into differing channels	0.0	[0.0‑1.0]	cycles
polar	Polar coordinate for spatialising audio into differing channels	0	[0.0‑1.0]	half-cycles
pitch_hi	Pitch range maximum in semitones	0.1	-	unitless
pitch_lo	Pitch range minimum in semitones	0	-	unitless
pitch_shift	Default shift in semitones	0.0	[0.0‑24.0]	semitones
equal_loudness_normalisation	Boolean, whether or not the spectrum is Equalised such that single tones at different frequencies should sound equally loud (to the average listener, at a default loudness of 70 phon), following ISO:226.	False	-	-

volume_envelope parameter group

Define the note volume envelope applied to the samples A,D,S & R correspond to ‘attack’, ‘decay’, ‘sustain’ and ‘release’. ‘ADSR’ is a common parametrisation in sound synthesis, Find out more e.g. at this link.

Parameter	Description	Default Value	Default Range	Unit
A	Attack, how long it takes for a sound to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the sounds volume to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the volume level (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long the tone takes to finally die away once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total amplitude level of the envelope from 0 to 1, contolling maximum volume of the note.	1.0	[0.0‑1.0]	fraction

pitch_lfo parameter group

Controls for the 'Low Frequency Oscillator' (LFO) used to modulate pitch of notes at rhythmic frequencies. In music this is often referred to as 'vibrato'.

Parameter	Description	Default Value	Default Range	Unit
use	Switch feature on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	sine	-	-
amount	the amplitude of the maximal pitch oscillation from the underlying pitch	0.5	[0‑2]	semitones
freq	Base frequency of the LFO oscillations.	3	[1.0‑12.0]	Hz
freq_shift	Shift relative to the base LFO frequency.	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction

volume_lfo parameter group

Controls for the 'Low Frequency Oscillator' (LFO) used to modulate volume of notes at rhythmic frequencies. In music this is often referred to as 'tremolo'.

Parameter	Description	Default Value	Default Range	Unit
use	switch volume LFO effects on or off	False	-	-
wave	Type of waveform used for the oscillator. As with Synthesizer oscillators can be sawtooth ('saw'), square ('square'), sinusoid ('sine'), triangle ('tri') or noise ('noise').	sine	-	-
amount	The amplitude of the maximal volume oscillation from the underlying pitch	0.5	[0‑1]	unitless
freq	Base frequency of the LFO oscillations.	3	[1.0‑12.0]	Hz
freq_shift	Shift relative to the base LFO frequency	0	[0.0‑3.0]	octave
phase	The phase of the LFO oscillations, defined in terms of fraction of a whole cycle.	random	-	-
A	Attack, how long it takes for the LFO depth to rise to 100% of the level after it’s triggered.	0.0	['1e‑2'‑20.0]	seconds
D	Decay, how long it takes for the LFO depth to die down to the Sustain value after the Attack period.	0.1	['1e‑2'‑20.0]	seconds
S	Sustain, the LFO depth (from 0 to 1.0) maintained after the Decay period, while the note is held.	1.0	[0.0‑1.0]	fraction
R	Release, how long LFO depth takes to finally die to 0 once the note is released.	0.0	['1e‑2'‑20]	seconds
Ac	Curvature of the attack portion of the envelope. Values from -1 to 1, positive indicates increases quickly then slow, negative slowly then quick. a value of 0 is a linear attack, increasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Dc	Curvature of the Decay portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear decay, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
Rc	Curvature of the release portion of the envelope. Values from -1 to 1, positive indicates decreases quickly then slow, negative slowly then quick. a value of 0 is a linear release, decreasing at a constant rate.	0.0	[‑1.0‑1.0]	unitless
level	Total level of the envelope from 0 to 1, contolling maximum depth of the LFO.	1	[0.0‑1.0]	fraction