Core

Generators

class maxiOsc

Public Functions

double square(double frequency)

Square wave oscillator

Parameters: frequency – in Hz

double sinewave(double frequency)

Sine wave oscillator

Parameters: frequency – in Hz

double coswave(double frequency)

Cosine wave oscillator

Parameters: frequency – in Hz

double saw(double frequency)

Saw wave oscillator

Parameters: frequency – in Hz

double phasor(double frequency)

A ramp rising from 0 to 1

Parameters: frequency – in Hz

double phasorBetween(double frequency, double startphase, double endphase)

A ramp rising from 0 to 1

Parameters

frequency – in Hz
startPhase – the start point of the phasor (0-1)
endPhase – the end point of the phasor (0-1)

double triangle(double frequency)

Triangle oscillator

Parameters: frequency – in Hz

double pulse(double frequency, double duty)

Pulse wave oscillator

Parameters

frequency – in Hz
duty – Pulse width (0-1)

double impulse(double frequency)

Impulse generator

Parameters: frequency – in Hz

double sinebuf(double frequency)

Fast sine wave oscillator, generated from a wavetable with linear interpolation

Parameters: frequency – in Hz

double noise(): White noise generator

double sinebuf4(double frequency)

Fast sine wave oscillator, generated from a wavetable with quadratic interpolation

Parameters: frequency – in Hz

double sawn(double frequency)

Anti-aliases saw wave oscillator

Parameters: frequency – in Hz

void phaseReset(double phaseIn)

Set the phase of the oscillator

Parameters: phaseIn – The phase, from 0 to 1

class maxiPolyBLEP

Anti-aliased oscillators;

Public Types

using Waveform = PolyBLEP::Waveform: Waveform types: SINE, COSINE, TRIANGLE, SQUARE, RECTANGLE, SAWTOOTH, RAMP, MODIFIED_TRIANGLE, MODIFIED_SQUARE, HALF_WAVE_RECTIFIED_SINE, FULL_WAVE_RECTIFIED_SINE, TRIANGULAR_PULSE, TRAPEZOID_FIXED, TRAPEZOID_VARIABLE

Public Functions

inline maxiPolyBLEP(): Constructor

inline double play(double freq)

play the oscillator

Parameters: freq – frequency in Hz

inline void setWaveform(Waveform waveform): Set the waveform type

inline void setPulseWidth(double pw): Change the pulse width (0 <= pw <= 1)

class maxiEnvGen

An envelope generator.

Public Functions

inline double play(double trigger)

Get the latest value of the envelope

Parameters: trigger – A positive zero crossing (or constant 1) starts the envelope

inline bool setup(DOUBLEARRAY levels, DOUBLEARRAY times, DOUBLEARRAY curves, bool looping, bool allowRetrigger = false)

Configure the envelope generator

Parameters

levels – An array of levels
times – An array of times between the levels, in milliseconds. To make the envelope hold until the first negative zero crossing, use maxiEnvGen::HOLD as the time. Only one hold segment is allowed.
curves – An array of exponential curve values to shape each segment (1 = straight, 2= squared, 0.5 = square root etc)
looping – True if the envelope should infinitely repeat
allowRetrigger – Set to true if the envelope should allow retriggering before it is finished, or false if the envelope should always reach the end before being allowed to restart Example C++ usage env.setup({0,1,0},{100,400}, {0.5,1}, false). levels should be one element longer than times and curves

Returns

True if the configuration was successful

inline void reset(): Restart the envelope immeadiately

inline void resetAndArm(): Stop the envelope and wait for a new trigger to start it

inline bool setLevel(size_t index, double value)

Set the level of a segment of the envelope

Parameters

index – The index of the level
value – The new level

inline bool setCurve(size_t index, double value)

Set the curve of a segment of the envelope

Parameters

index – The index of the segment
value – The new curve value

inline bool setTime(size_t index, double value)

Set the length of a segment of the envelope

Parameters

index – The index of the segment
value – The new length (in ms)

inline void setupAR(const double attack, const double release)

Helper function to create a triangular envelope

Parameters

attack – Rise time in ms
release – Fall time in ms

inline void setupASR(const double attack, const double release)

Helper function to create a triangular(ish) envelope with sustain section at peak The sustain section will end when the trigger input drops below 0

Parameters

attack – Rise time in ms
release – Fall time in ms

inline void setupADSR(const double attack, const double decay, const double sustain, const double release)

Helper function to create an attack-decay-sustain-release envelope The sustain section will end when the trigger input drops below 0 The envelope will rise from 0 to 1 in the attack segment, then drop to the sustain level before falling to 0.

Parameters

attack – Rise time in ms
decay – Decay time in ms
sustain – Sustain level
release – Fall time in ms

inline void setRetrigger(const bool val)

Set the envelope to retrigger or not

Parameters: val – True is the envelope should retrigger, false if not

inline bool getRetrigger(): Find out if the envelope retriggers

inline void setLoop(const bool val)

Set the envelope to loop or not

Parameters: val – True is the envelope should loop, false if not

inline bool getLoop(): Find out if the envelope loops

Filters

class maxiSVF

State Variable Filter

algorithm from http://www.cytomic.com/files/dsp/SvfLinearTrapOptimised.pdf usage:

filter.setCutoff(param1); filter.setResonance(param2);

w = filter.play(w, 0.0, 1.0, 0.0, 0.0);

Public Functions

inline void setCutoff(double cutoff)

Set the cutoff frequency

Parameters: cutoff – Cuttoff frequency (20 < cutoff < 20000)

inline void setResonance(double q)

Set the resonance of the filter

Parameters: q – From 0 upwards, starts to ring from 2-3ish, cracks a bit around 10

inline double play(double w, double lpmix, double bpmix, double hpmix, double notchmix)

run the filter, and get a mixture of lowpass, bandpass, highpass and notch outputs

Parameters

w – The signal to be filtered
lpmix – the amount of low pass filtering (0-1)
bpmix – the amount of bandpass pass filtering (0-1)
hpmix – the amount of high pass filtering (0-1)
notchmix – the amount of notch filtering (0-1)

class maxiBiquad

Biquad filters based on http://www.earlevel.com/main/2011/01/02/biquad-formulas/ and https://ccrma.stanford.edu/~jos/fp/Direct_Form_II.html

Public Types

enum filterTypes

A variety of filter types

Values:

enumerator LOWPASS

enumerator HIGHPASS

enumerator BANDPASS

enumerator NOTCH

enumerator PEAK

enumerator LOWSHELF

enumerator HIGHSHELF

Public Functions

inline double play(double input)

Process a signal through the filter

Parameters: input – A signal

inline void set(filterTypes filtType, double cutoff, double Q, double peakGain)

Configure the filter

Parameters

filtType – The type of filter, set from maxiBiquad::filterTypes
cutoff – The filter cutoff frequency in Hz
Q – The resonance of the filter
peakGain – The gain of the filter (only used for PEAK, HIGHSHELF and LOWSHELF)

Dynamics

class maxiDynamics

The class provides a range of dynamics processing: downward and upward compression, downward and upward expansion, sidechaining, attack and release, lookahead and peak or RMS detection

Public Functions

inline double play(double sig, double control, double thresholdHigh, double ratioHigh, double kneeHigh, double thresholdLow, double ratioLow, double kneeLow)

This functions compands the signal, providing download compression or upward expansion above an upper thresold, and upward compression or downward expansion below a lower threshold.

Parameters

sig – The input signal to be companded
control – This signal is used to trigger the compander. Use it for sidechaining, or if no sidechain is needed, use the same signal for this and the input signal
thresholdHigh – The high threshold, in Dbs
ratioHigh – The ratio for companding above the high threshold
kneeHigh – The size of the knee for companding above the high threshold (in Dbs)
thresholdLow – The low threshold, in Dbs
ratioLow – The ratio for companding below the low threshold
kneeLow – The size of the knee for companding below the low threshold (in Dbs)

Returns

a companded signal

inline double compress(double sig, double threshold, double ratio, double knee)

Compress a signal (using downward compression)

Parameters

sig – The input signal to be compressed
threshold – The threshold, in Dbs
ratio – The compression ratio (>1 provides compression, <1 provides expansion)
knee – The size of the knee (in Dbs)

Returns

a compressed signal

inline double sidechainCompress(double sig, double control, double threshold, double ratio, double knee)

Compress a signal with sidechaining (using downward compression)

Parameters

sig – The input signal to be compressed
control – The sidechain signal
threshold – The threshold, in Dbs
ratio – The compression ratio (>1 provides compression, <1 provides expansion)
knee – The size of the knee (in Dbs)

Returns

a compressed signal

inline double compandAbove(double sig, double control, double threshold, double ratio, double knee)

Compand a signal, using detection above a threshold (provides downward compression or upward expansion)

Parameters

sig – The input signal to be compressed
control – The sidechain signal
threshold – The threshold, in Dbs
ratio – The compression ratio (>1 provides compression, <1 provides expansion)
knee – The size of the knee (in Dbs)

Returns

a companded signal

inline double compandBelow(double sig, double control, double threshold, double ratio, double knee)

Compand a signal, using detection below a threshold (provides upward compression or downward expansion)

Parameters

sig – The input signal to be compressed
control – The sidechain signal
threshold – The threshold, in Dbs
ratio – The compression ratio (>1 provides compression, <1 provides expansion)
knee – The size of the knee (in Dbs)

Returns

a companded signal

inline void setAttackHigh(double attack)

Set the attack time for the high threshold. This is the amount of time over which the ratio moves from 1 to its full value, following the input analyser going over the threshold.

Parameters: attack – The attack time (in milliseconds)

inline void setReleaseHigh(double release)

Set the release time for the high threshold. This is the amount of time over which the ratio moves from its full value to 1, following the input analyser going under the threshold.

Parameters: release – The release time (in milliseconds)

inline void setAttackLow(double attack)

Set the attack time for the low threshold. This is the amount of time over which the ratio moves from 1 to its full value, following the input analyser going under the threshold.

Parameters: attack – The attack time (in milliseconds)

inline void setReleaseLow(double release)

Set the release time for the low threshold. This is the amount of time over which the ratio moves from its full value to 1, following the input analyser going over the threshold.

Parameters: release – The release time (in milliseconds)

inline void setLookAhead(double length)

The look ahead creates a delay on the input signal, meaning that that the signal is compressed according to event that have already happened in the control signal. This can be useful for limiting and catching fast transients.

Parameters: length – The amount of time the compressor looks ahead (in milliseconds)

inline double getLookAhead()

Returns: the look ahead time (in milliseconds)

inline void setRMSWindowSize(double winSize)

Set the size of the RMS window. Longer times give a slower response

Parameters: winSize – The size of the window (in milliseconds)

inline void setInputAnalyser(ANALYSERS mode): Set the method by which the compressor analyses the control input \mode maxiDynamics::PEAK for peak analysis, maxiDynamics::RMS for rms analysis

Effects

class maxiDelayline

A delay line

Public Functions

double dl(double input, int size, double feedback)

Apply a delay to a signal

Parameters

input – a signal,
size – the size of the delay in samples
feedback – the amount of feedback

double dlFromPosition(double input, int size, double feedback, int position)

Apply a delay to a signal, reading from a specific position in the buffer

Parameters

input – a signal,
size – the size of the delay in samples
feedback – the amount of feedback
position – the position in the buffer (in samples)

class maxiNonlinearity

Various ways to distort signals

Public Functions

inline double atanDist(const double in, const double shape)

atan distortion, see http://www.musicdsp.org/showArchiveComment.php?ArchiveID=104

Parameters

in – A signal
shape – from 1 (soft clipping) to infinity (hard clipping)

inline double fastAtanDist(const double in, const double shape)

Faster but ‘lower quality’ version of atan distortion

Parameters

in – A signal
shape – from 1 (soft clipping) to infinity (hard clipping)

inline double softclip(double x)

Cliping with nicer harmonics

Parameters: x – A signal

inline double hardclip(double x)

Cliping with nastier harmonics

Parameters: x – A signal

inline double asymclip(double x, double a, double b)

asymmetric clipping: chose the shape of curves for both positive and negative values of x try it here https://www.desmos.com/calculator/to6eixatsa

Parameters

x – A signal
a – Exponent for the positive curve
b – Exponent for the negative curve

inline double fastatan(double x)

Fast atan distortion

Parameters: x – A signal

class maxiSampleAndHold

Sample and hold effect: samples the input signal periodically and outputs that value

Public Functions

inline double sah(double sigIn, double holdTimeMs)

Process a signal

Parameters

sigIn – a signal
holdTimeMs – The length of the sampling period

Returns

the sampled signal

Analysis

class maxiZeroCrossingDetector

Detect positive zero-crossings: the point in time when a signal transitions from 0 or less, to above zero

Public Functions

inline bool zx(double x)

Returns true when a positive zero-crossing occurs, othersize false

Parameters: x – A signal

class maxiZeroCrossingRate

Calculate the zero crossing rate of a signal This is a fairly crude measure of frequency, which is confounded by complex waveforms and noise

Public Functions

inline double play(double signal)

Calculate the zero cross rate

Parameters: signal – a signal
Returns: the zero crossing rate in Hz

class maxiRMS

Calculate the Root Mean Square of a signal over a window of time This is a good measurement of the amount of power in a signal

Public Functions

inline void setup(double maxLength, double windowSize)

Configure the analyser

Parameters

maxLength – The maximum length of time to analyse (ms)
windowSize – The size of the window of time to analyse initially (ms, <= maxLength)

inline void setWindowSize(double newWindowSize)

Set the size of the analysis window

Parameters: newWindowSize – the size of the analysis window (in ms). Large values will smooth out the measurement, and make it less responsive to transients

inline double getWindowSize(): Find out the size of the analysis window (in ms)

Sequencing

class maxiStep

Pull sequential values from an array

Public Functions

inline double pull(const double trigSig, DOUBLEARRAY values, double step)

Take values from the array when triggered

Parameters

trigSig – A signal to trigger a new value on a positive zero crossing
values – An array of values \step The amount that the array index should increase after pulling a new value. This wraps around to zero at the end of the array

inline double getIndex(): Get the current array index

Utility Functions

class maxiPoll

Poll values to stdout at regular intervals

Public Functions

inline double poll(double val, double frequency = 4, string txt = "", string end = "\n")

Parameters

val – The value to poll
frequency – How often to print this value (Hz)
txt – Additional text to br printed before the value

Returns

the value being polled, so this can used as a pass-through function e.g. filter.play(obj.poll(osc.saw(2)),0.5)

class maxiConvert

Conversion functions

Public Static Functions

static double mtof(int midinote)

Convert from MIDI note number to frequency (Hz)

Parameters: midinote – A MIDI note number

static inline size_t msToSamps(double timeMs)

Convert from milliseconds to samples

Parameters: timeMs – The number of milliseconds

static inline double sampsToMs(size_t samples)

Convert from samples to milliseconds

Parameters: samples – The number of samples

static inline double ampToDbs(double amp)

Convert from amplitude to decibels

Parameters: amp – Amplitude

static inline double dbsToAmp(double dbs)

Convert from decibels to amplitude

Parameters: dbs – Decibels

class maxiRingBuf

A ring buffer. This enables you to look at the last N values in a time series.

Public Functions

inline void setup(size_t N)

Allocate memory for the buffer

Parameters: N – The maximum length of the buffer

inline void push(double x)

Add the latest value to the buffer

Parameters: x – A value

inline size_t size()

Returns: The size of the buffer

inline double head()

Returns: the value at the front of the buffer

inline double tail(size_t N)

Parameters: N – The size of the window, N < the size of the buffer
Returns: the oldest value in the buffer, for a particular window size

inline double reduce(size_t N, reduceFunction func, double initval)

Apply a function of the previous N values in the buffer

Parameters

N – The number of values in the window
func – A function in the form double func(double previousResult, double nextValue)
initval – The initial value to pass into the function (usually 0)

Returns

The last result of the function, after passing in all values from the window Example: this function will sum the values in the window: auto sumfunc = [](double val, double n) {return val + n;};