Zero-latency, highly optimized allpass-based phaser. More...

#include <Phaser.h>

Collaboration diagram for dspark::Phaser< T >:

[legend]

Classes
struct	FirstOrderAllpass

Public Member Functions
	~Phaser ()=default

void	prepare (const AudioSpec &spec)
	Prepares the phaser and allocates internal state blocks.

void	processBlock (AudioBufferView< T > buffer) noexcept
	Processes an audio block in-place.

void	reset () noexcept
	Clears internal DSP state and history buffers. Call this when transport stops or playback jumps.

void	setRate (T hz) noexcept
	Sets the speed of the phaser sweep.

void	setDepth (T amount) noexcept
	Sets how wide the frequency sweep is.

void	setMix (T dryWet) noexcept
	Balances the unprocessed and processed signal.

void	setStages (int count) noexcept
	Configures the intensity/color of the phaser via filter stages.

void	setFeedback (T amount) noexcept
	Injects phase-shifted signal back into the input for resonance.

void	setStereoSpread (T amount) noexcept
	Sets the stereo phase spread of the sweep LFO.

void	setCenterFrequency (T hz) noexcept
	Defines the midpoint of the logarithmic frequency sweep.

void	setFrequencyRange (T minHz, T maxHz) noexcept
	Explicitly defines the sweep boundaries.

void	setLfoWaveform (typename Oscillator< T >::Waveform wf) noexcept
	Changes the geometric shape of the LFO modulation.

int	getStages () const noexcept
	Retrieves the active stage count.

T	getRate () const noexcept
	Retrieves the current sweep rate.

std::vector< uint8_t >	getState () const
	Serializes the parameter state (setup/UI threads; allocates).

bool	setState (const uint8_t *data, size_t size)
	Restores parameters from a blob (tolerant; rejects foreign ids).

Static Public Attributes
static constexpr int	kMaxStages = 12

Protected Attributes
AudioSpec	spec_ {}

std::atomic< T >	rate_ { T(0.5) }

std::atomic< T >	depth_ { T(0.8) }

std::atomic< T >	mix_ { T(0.5) }

std::atomic< T >	feedback_ { T(0) }

std::atomic< T >	minFreq_ { T(200) }

std::atomic< T >	maxFreq_ { T(6000) }

std::atomic< int >	numStages_ { 4 }

std::atomic< typename Oscillator< T >::Waveform >	lfoWaveform_ { Oscillator<T>::Waveform::Sine }

std::atomic< T >	stereoSpread_ { T(0) }

bool	prepared_ { false }

T	currentDepth_ { T(0.8) }

T	currentFb_ { T(0) }

T	smoothCoef_ { T(0.01) }

T	lastSpread_ { T(-1) }

int	lastStages_ { kMaxStages }

std::array< FirstOrderAllpass, kMaxStages >	stages_ {}

std::array< T, kMaxChannels >	fbState_ {}

Oscillator< T >	lfo_

Oscillator< T >	lfoR_

DryWetMixer< T >	mixer_

Static Protected Attributes
static constexpr int	kMaxChannels = 16

Detailed Description

template<FloatType T>
class dspark::Phaser< T >

Zero-latency, highly optimized allpass-based phaser.

Employs parameter smoothing to prevent zipper noise and utilizes fast math approximations for real-time performance.

Template Parameters

T	Sample type (must satisfy FloatType concept, e.g., float or double).

Definition at line 66 of file Phaser.h.

Constructor & Destructor Documentation

◆ ~Phaser()

template<FloatType T>

dspark::Phaser< T >::~Phaser ( )

default

Member Function Documentation

◆ getRate()

template<FloatType T>

T dspark::Phaser< T >::getRate ( ) const

inlinenoexcept

Retrieves the current sweep rate.

Returns: Rate in Hz.

Definition at line 379 of file Phaser.h.

◆ getStages()

template<FloatType T>

int dspark::Phaser< T >::getStages ( ) const

inlinenoexcept

Retrieves the active stage count.

Returns: Number of stages.

Definition at line 376 of file Phaser.h.

◆ getState()

template<FloatType T>

std::vector< uint8_t > dspark::Phaser< T >::getState ( ) const

inline

Serializes the parameter state (setup/UI threads; allocates).

Definition at line 383 of file Phaser.h.

◆ prepare()

template<FloatType T>

void dspark::Phaser< T >::prepare ( const AudioSpec & spec )

inline

Prepares the phaser and allocates internal state blocks.

An invalid spec (non-positive or non-finite fields) is a no-op that keeps the previous state.

Parameters

spec	Hardware audio specifications (sample rate, block size).

Definition at line 83 of file Phaser.h.

◆ processBlock()

template<FloatType T>

void dspark::Phaser< T >::processBlock ( AudioBufferView< T > buffer )

inlinenoexcept

Processes an audio block in-place.

Parameters

buffer The AudioBufferView containing channels to process.

Definition at line 109 of file Phaser.h.

◆ reset()

template<FloatType T>

void dspark::Phaser< T >::reset ( )

inlinenoexcept

Clears internal DSP state and history buffers. Call this when transport stops or playback jumps.

Definition at line 231 of file Phaser.h.

◆ setCenterFrequency()

template<FloatType T>

void dspark::Phaser< T >::setCenterFrequency ( T hz )

inlinenoexcept

Defines the midpoint of the logarithmic frequency sweep.

Keeps the current sweep RATIO and recenters it geometrically. Callable before prepare() (a 20 kHz ceiling stands in for Nyquist until the rate is known; the per-sample cutoff clamp covers later rate changes anyway).

Parameters

hz	Center frequency in Hertz (non-positive or non-finite values are ignored).

Definition at line 332 of file Phaser.h.

◆ setDepth()

template<FloatType T>

void dspark::Phaser< T >::setDepth ( T amount )

inlinenoexcept

Sets how wide the frequency sweep is.

Parameters

amount Range: [0.0 (static), 1.0 (full spectrum)]. Non-finite values are ignored.

Definition at line 267 of file Phaser.h.

◆ setFeedback()

template<FloatType T>

void dspark::Phaser< T >::setFeedback ( T amount )

inlinenoexcept

Injects phase-shifted signal back into the input for resonance.

Parameters

amount Feedback gain. Range: [-0.99, 0.99]. Negative values alter the vocal formant shape. Non-finite values are ignored.

Definition at line 300 of file Phaser.h.

◆ setFrequencyRange()

template<FloatType T>

void dspark::Phaser< T >::setFrequencyRange	(	T	minHz,
		T	maxHz
	)

inlinenoexcept

Explicitly defines the sweep boundaries.

Parameters

minHz	Lower limit of the allpass cutoff sweep.
maxHz	Upper limit of the allpass cutoff sweep. Non-finite values are ignored.

Definition at line 353 of file Phaser.h.

◆ setLfoWaveform()

template<FloatType T>

void dspark::Phaser< T >::setLfoWaveform ( typename Oscillator< T >::Waveform wf )

inlinenoexcept

Changes the geometric shape of the LFO modulation.

Parameters

wf	Target waveform (e.g., Sine, Triangle; wild enum values clamp).

Definition at line 367 of file Phaser.h.

◆ setMix()

template<FloatType T>

void dspark::Phaser< T >::setMix ( T dryWet )

inlinenoexcept

Balances the unprocessed and processed signal.

Parameters

dryWet Range: [0.0 (fully dry), 1.0 (fully wet)]. Non-finite values are ignored.

Definition at line 278 of file Phaser.h.

◆ setRate()

template<FloatType T>

void dspark::Phaser< T >::setRate ( T hz )

inlinenoexcept

Sets the speed of the phaser sweep.

Parameters

hz	LFO frequency in Hertz. Range: [0.01, 20.0]. Non-finite values are ignored.

Definition at line 256 of file Phaser.h.

◆ setStages()

template<FloatType T>

void dspark::Phaser< T >::setStages ( int count )

inlinenoexcept

Configures the intensity/color of the phaser via filter stages.

Parameters

count Number of allpass stages. Range: [1, 12]. Evens (2,4,6) are standard.

Definition at line 290 of file Phaser.h.

◆ setState()

template<FloatType T>

bool dspark::Phaser< T >::setState	(	const uint8_t *	data,
		size_t	size
	)

inline

Restores parameters from a blob (tolerant; rejects foreign ids).

Definition at line 400 of file Phaser.h.

◆ setStereoSpread()

template<FloatType T>

void dspark::Phaser< T >::setStereoSpread ( T amount )

inlinenoexcept

Sets the stereo phase spread of the sweep LFO.

Offsets the right channel's LFO phase against the left, like classic hardware stereo phasers. 0 = mono-coherent sweep (both channels move together), 1 = fully opposed (180-degree) sweep.

template<FloatType T>

std::array<FirstOrderAllpass, kMaxStages> dspark::Phaser< T >::stages_ {}

protected

Definition at line 448 of file Phaser.h.

◆ stereoSpread_

template<FloatType T>

std::atomic<T> dspark::Phaser< T >::stereoSpread_ { T(0) }

protected

Definition at line 431 of file Phaser.h.

The documentation for this class was generated from the following file:

Effects/Phaser.h

Classes

Public Member Functions

Static Public Attributes

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ~Phaser()

Member Function Documentation

◆ getRate()

◆ getStages()

◆ getState()

◆ prepare()

◆ processBlock()

◆ reset()

◆ setCenterFrequency()

◆ setDepth()

◆ setFeedback()

◆ setFrequencyRange()

◆ setLfoWaveform()

◆ setMix()

◆ setRate()

◆ setStages()

◆ setState()

◆ setStereoSpread()

Member Data Documentation

◆ currentDepth_

◆ currentFb_

◆ depth_

◆ fbState_

◆ feedback_

◆ kMaxChannels

◆ kMaxStages

◆ lastSpread_

◆ lastStages_

◆ lfo_

◆ lfoR_

◆ lfoWaveform_

◆ maxFreq_

◆ minFreq_

◆ mix_

◆ mixer_

◆ numStages_

◆ prepared_

◆ rate_

◆ smoothCoef_

◆ spec_

◆ stages_

◆ stereoSpread_