pulp::signal::fdn Namespace Reference

Classes
struct	ParamSpec
struct	ModeConfig
class	AllpassStage
class	AllpassCascade
class	SanitizedBiquadState
class	FracDelayT
class	HermiteHistory
struct	EqBand
class	LoopEq
class	FluxBank
class	XorShift32
class	MeanRevertingWalk
class	PhaseOsc
class	QuadratureBank
class	DelayModulationBank
class	PositionRing
class	ButterworthPair
class	ButterworthState
class	StereoPositionRing
struct	StereoSection
struct	StereoSectionLanes
class	StereoBiquadState
class	MultirateBridge
class	ShimmerBank
class	TransientDucker
class	EnsembleChorus
struct	TankControls
class	FdnTank

Typedefs
using	FracDelay = FracDelayT<float>

Enumerations
enum class	Tier { network = 0 , classic }
enum class	Param {   decay = 0 , size , predelay , damp_hi ,   damp_lo , diffusion , mod , shimmer ,   drive , bloom , width , tank_rate ,   count }
enum class	Mode {   room = 0 , hall , galaxy , shimmer ,   lofi , count }

Functions
constexpr const ModeConfig &	mode_config (Mode m)
constexpr double	mode_default (Mode mode, Param param)
double	hermite4 (double y0, double y1, double y2, double y3, double t)
template<typename T>
T	hermite4_t (T y0, T y1, T y2, T y3, T t)
std::array< EqBand, kNumEqBands >	default_eq_bands ()
double	mod_depth_shrink (double decay_seconds)
template<typename T>
T	finite_or_zero (T value)
void	apply_width (double &l, double &r, double width)
double	soft_limit (double x)
float	tanh_rational (float x)
float	soft_limit (float x)
double	bloom_authority (double decay_seconds)
template<typename T>
void	hadamard16 (std::array< T, kNumChannels > &v)
template<typename T>
T	post_hadamard_guard (T value)
double	damping_state_step (double input, double coefficient, double &state)
double	lipschitz_tanh (double v) noexcept
	A [3/2] Padé tanh that is 1-LIPSCHITZ and bounded — the saturator to reach for inside a feedback loop.

Variables
constexpr int	kNumChannels = 16
constexpr int	kMaxDiffusionStages = 8
constexpr int	kNumEqBands = 10
constexpr int	kNumShimmerGrains = 4
constexpr int	kNumEnsembleLfos = 6
constexpr std::array< int, kNumChannels >	kChannelPrimes
constexpr std::array< double, 8 >	kTankRates
constexpr int	kNumTankRates = static_cast<int>(kTankRates.size())
constexpr double	kMaxTankRate = 96000.0
constexpr std::array< double, 8 >	kRateMakeupDb
constexpr double	kDelayMinSeconds = 0.010
constexpr double	kDelayMaxSeconds = 0.090
constexpr double	kSizeScaleMin = 0.5
constexpr double	kSizeScaleMax = 5.0 / 3.0
constexpr double	kDelayExponent = 2.0
constexpr int	kPreDiffusionStages = 4
constexpr int	kLoopDiffusionStages = 4
constexpr double	kPreDiffusionG = 0.70
constexpr double	kLoopDiffusionG = 0.45
constexpr double	kPreDiffusionBaseMs = 12.0
constexpr double	kLoopDiffusionBaseMs = 7.0
constexpr double	kDiffusionStageShrink = 0.70710678118654752
constexpr double	kFlutterDepth = 0.02
constexpr double	kFlutterRateMinHz = 0.13
constexpr double	kFlutterRateMaxHz = 0.71
constexpr double	kModSineMix = 0.6
constexpr double	kModWalkMix = 0.4
constexpr double	kModRateMinHz = 0.10
constexpr double	kModRateMaxHz = 1.50
constexpr double	kModMaxFraction = 0.0035
constexpr double	kModShrinkFullSeconds = 2.0
constexpr double	kModShrinkMinSeconds = 20.0
constexpr double	kModShrinkFloor = 0.25
constexpr double	kWalkReversion = 0.004
constexpr double	kWalkStep = 0.09
constexpr double	kDampingScale = 1.0
constexpr double	kDampHiMinHz = 1200.0
constexpr double	kDampHiMaxHz = 192000.0
constexpr double	kDampLoMinHz = 10.0
constexpr double	kDampLoMaxHz = 500.0
constexpr double	kDampCurve = 1.6
constexpr double	kFluxMaxDb = 3.0
constexpr double	kFluxDefaultDb = 0.5
constexpr double	kFluxBaseMinHz = 300.0
constexpr double	kFluxBaseMaxHz = 6000.0
constexpr double	kFluxSpreadOctaves = 0.7
constexpr double	kFluxIntervalMinMs = 120.0
constexpr double	kFluxIntervalMaxMs = 250.0
constexpr double	kFluxGlideMs = 90.0
constexpr double	kFluxQ = 8.0
constexpr double	kShimmerGrainMinMs = 40.0
constexpr double	kShimmerGrainMaxMs = 60.0
constexpr double	kShimmerToneHz = 8000.0
constexpr double	kShimmerMaxWeight = 0.6
constexpr double	kGainCeil = 0.999
constexpr double	kBloomAuthorityMinSeconds = 1.0
constexpr double	kBloomAuthorityMaxSeconds = 20.0
constexpr double	kDuckFastMs = 3.0
constexpr double	kDuckSlowMs = 40.0
constexpr double	kDuckAmount = 0.3
constexpr double	kDuckKnee = 1.5
constexpr double	kEnsembleBaseMs = 5.0
constexpr double	kEnsembleDepthMs = 1.6
constexpr double	kEnsembleRateMinHz = 0.11
constexpr double	kEnsembleRateMaxHz = 0.83
constexpr double	kEnsembleWetMix = 0.35
constexpr double	kDriveMakeupDb = 3.0
constexpr double	kWetLimiterHeadroom = 2.0
constexpr double	kButterworthQ0 = 0.5412
constexpr double	kButterworthQ1 = 1.3065
constexpr double	kAaCutoffFraction = 0.45
constexpr int	kHermiteGuard = 8
constexpr double	kTankInputLpThresholdHz = 18000.0
constexpr double	kTankInputLpFraction = 0.42
constexpr double	kPostHadamardCeil = 4.0
constexpr double	kSanityCeil = 10.0
constexpr double	kSmoothingMs = 5.0
constexpr int	kControlRateSamples = 32
constexpr int	kMaxBlockSamples = kControlRateSamples
constexpr int	kHealIntervalSamples = 32
constexpr std::size_t	kRingStaggerSamples = 37 * 16
constexpr int	kOscReanchorSamples = 4096
constexpr int	kNumParams = static_cast<int>(Param::count)
constexpr std::array< ParamSpec, kNumParams >	kParamSpecs
constexpr int	kNumModes = static_cast<int>(Mode::count)
constexpr std::array< ModeConfig, kNumModes >	kModeConfigs

Typedef Documentation

FracDelay

using pulp::signal::fdn::FracDelay = FracDelayT<float>

Enumeration Type Documentation

Mode

enum class pulp::signal::fdn::Mode

strong

Enumerator
room
hall
galaxy
shimmer
lofi
count

Param

enum class pulp::signal::fdn::Param

strong

Enumerator
decay
size
predelay
damp_hi
damp_lo
diffusion
mod
shimmer
drive
bloom
width
tank_rate
count

Tier

enum class pulp::signal::fdn::Tier

strong

Enumerator
network
classic

Function Documentation

apply_width()

void pulp::signal::fdn::apply_width ( double & l, double & r, double width )

inline

bloom_authority()

double pulp::signal::fdn::bloom_authority ( double decay_seconds )

inline

damping_state_step()

double pulp::signal::fdn::damping_state_step ( double input, double coefficient, double & state )

inline

default_eq_bands()

std::array< EqBand, kNumEqBands > pulp::signal::fdn::default_eq_bands ( )

inline

finite_or_zero()

template<typename T>

T pulp::signal::fdn::finite_or_zero ( T value )

inline

hadamard16()

template<typename T>

void pulp::signal::fdn::hadamard16 ( std::array< T, kNumChannels > & v )

inline

hermite4()

double pulp::signal::fdn::hermite4 ( double y0, double y1, double y2, double y3, double t )

inline

hermite4_t()

template<typename T>

T pulp::signal::fdn::hermite4_t ( T y0, T y1, T y2, T y3, T t )

inline

lipschitz_tanh()

double pulp::signal::lipschitz_tanh ( double v )

inlinenoexcept

A [3/2] Padé tanh that is 1-LIPSCHITZ and bounded — the saturator to reach for inside a feedback loop.

This is a different curve from FastMath::tanh, not a cheaper one, and the difference is the whole reason it exists. FastMath::tanh chases fidelity to std::tanh; this one is chosen for a property. Its derivative is (x^2-9)^2 / (9(3+x^2)^2), which is exactly 1 at the origin and strictly below 1 everywhere else, so it can never amplify — and the clamp at the point where the curve reaches unity (f(3) = 1 exactly) makes it bounded as well, without breaking that slope bound.

Inside a recursion those two properties are load-bearing. A saturator with small-signal gain above 1 (tanh(k*x) for k > 1 is the usual way to get one) silently raises the loop gain with it, which turns a decay-time control into a stability question; an unbounded one lets a self-oscillating loop settle only by growing more slowly than it decays. Two modules derived this same curve independently for those reasons — the character delay's dub feedback and the FDN reverb's in-loop drive — so it is defined once, here.

mod_depth_shrink()

double pulp::signal::fdn::mod_depth_shrink ( double decay_seconds )

inline

mode_config()

const ModeConfig & pulp::signal::fdn::mode_config ( Mode m )

inlineconstexpr

mode_default()

double pulp::signal::fdn::mode_default ( Mode mode, Param param )

inlineconstexpr

post_hadamard_guard()

template<typename T>

T pulp::signal::fdn::post_hadamard_guard ( T value )

inline

soft_limit() [1/2]

double pulp::signal::fdn::soft_limit ( double x )

inline

soft_limit() [2/2]

float pulp::signal::fdn::soft_limit ( float x )

inline

tanh_rational()

float pulp::signal::fdn::tanh_rational ( float x )

inline

Variable Documentation

kAaCutoffFraction

double pulp::signal::fdn::kAaCutoffFraction = 0.45

inlineconstexpr

kBloomAuthorityMaxSeconds

double pulp::signal::fdn::kBloomAuthorityMaxSeconds = 20.0

inlineconstexpr

kBloomAuthorityMinSeconds

double pulp::signal::fdn::kBloomAuthorityMinSeconds = 1.0

inlineconstexpr

kButterworthQ0

double pulp::signal::fdn::kButterworthQ0 = 0.5412

inlineconstexpr

kButterworthQ1

double pulp::signal::fdn::kButterworthQ1 = 1.3065

inlineconstexpr

kChannelPrimes

std::array<int, kNumChannels> pulp::signal::fdn::kChannelPrimes

inlineconstexpr

Initial value:

= {
    2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53}

kControlRateSamples

int pulp::signal::fdn::kControlRateSamples = 32

inlineconstexpr

kDampCurve

double pulp::signal::fdn::kDampCurve = 1.6

inlineconstexpr

kDampHiMaxHz

double pulp::signal::fdn::kDampHiMaxHz = 192000.0

inlineconstexpr

kDampHiMinHz

double pulp::signal::fdn::kDampHiMinHz = 1200.0

inlineconstexpr

kDampingScale

double pulp::signal::fdn::kDampingScale = 1.0

inlineconstexpr

kDampLoMaxHz

double pulp::signal::fdn::kDampLoMaxHz = 500.0

inlineconstexpr

kDampLoMinHz

double pulp::signal::fdn::kDampLoMinHz = 10.0

inlineconstexpr

kDelayExponent

double pulp::signal::fdn::kDelayExponent = 2.0

inlineconstexpr

kDelayMaxSeconds

double pulp::signal::fdn::kDelayMaxSeconds = 0.090

inlineconstexpr

kDelayMinSeconds

double pulp::signal::fdn::kDelayMinSeconds = 0.010

inlineconstexpr

kDiffusionStageShrink

double pulp::signal::fdn::kDiffusionStageShrink = 0.70710678118654752

inlineconstexpr

kDriveMakeupDb

double pulp::signal::fdn::kDriveMakeupDb = 3.0

inlineconstexpr

kDuckAmount

double pulp::signal::fdn::kDuckAmount = 0.3

inlineconstexpr

kDuckFastMs

double pulp::signal::fdn::kDuckFastMs = 3.0

inlineconstexpr

kDuckKnee

double pulp::signal::fdn::kDuckKnee = 1.5

inlineconstexpr

kDuckSlowMs

double pulp::signal::fdn::kDuckSlowMs = 40.0

inlineconstexpr

kEnsembleBaseMs

double pulp::signal::fdn::kEnsembleBaseMs = 5.0

inlineconstexpr

kEnsembleDepthMs

double pulp::signal::fdn::kEnsembleDepthMs = 1.6

inlineconstexpr

kEnsembleRateMaxHz

double pulp::signal::fdn::kEnsembleRateMaxHz = 0.83

inlineconstexpr

kEnsembleRateMinHz

double pulp::signal::fdn::kEnsembleRateMinHz = 0.11

inlineconstexpr

kEnsembleWetMix

double pulp::signal::fdn::kEnsembleWetMix = 0.35

inlineconstexpr

kFlutterDepth

double pulp::signal::fdn::kFlutterDepth = 0.02

inlineconstexpr

kFlutterRateMaxHz

double pulp::signal::fdn::kFlutterRateMaxHz = 0.71

inlineconstexpr

kFlutterRateMinHz

double pulp::signal::fdn::kFlutterRateMinHz = 0.13

inlineconstexpr

kFluxBaseMaxHz

double pulp::signal::fdn::kFluxBaseMaxHz = 6000.0

inlineconstexpr

kFluxBaseMinHz

double pulp::signal::fdn::kFluxBaseMinHz = 300.0

inlineconstexpr

kFluxDefaultDb

double pulp::signal::fdn::kFluxDefaultDb = 0.5

inlineconstexpr

kFluxGlideMs

double pulp::signal::fdn::kFluxGlideMs = 90.0

inlineconstexpr

kFluxIntervalMaxMs

double pulp::signal::fdn::kFluxIntervalMaxMs = 250.0

inlineconstexpr

kFluxIntervalMinMs

double pulp::signal::fdn::kFluxIntervalMinMs = 120.0

inlineconstexpr

kFluxMaxDb

double pulp::signal::fdn::kFluxMaxDb = 3.0

inlineconstexpr

kFluxQ

double pulp::signal::fdn::kFluxQ = 8.0

inlineconstexpr

kFluxSpreadOctaves

double pulp::signal::fdn::kFluxSpreadOctaves = 0.7

inlineconstexpr

kGainCeil

double pulp::signal::fdn::kGainCeil = 0.999

inlineconstexpr

kHealIntervalSamples

int pulp::signal::fdn::kHealIntervalSamples = 32

inlineconstexpr

kHermiteGuard

int pulp::signal::fdn::kHermiteGuard = 8

inlineconstexpr

kLoopDiffusionBaseMs

double pulp::signal::fdn::kLoopDiffusionBaseMs = 7.0

inlineconstexpr

kLoopDiffusionG

double pulp::signal::fdn::kLoopDiffusionG = 0.45

inlineconstexpr

kLoopDiffusionStages

int pulp::signal::fdn::kLoopDiffusionStages = 4

inlineconstexpr

kMaxBlockSamples

int pulp::signal::fdn::kMaxBlockSamples = kControlRateSamples

inlineconstexpr

kMaxDiffusionStages

int pulp::signal::fdn::kMaxDiffusionStages = 8

inlineconstexpr

kMaxTankRate

double pulp::signal::fdn::kMaxTankRate = 96000.0

inlineconstexpr

kModeConfigs

std::array<ModeConfig, kNumModes> pulp::signal::fdn::kModeConfigs

inlineconstexpr

Initial value:

= {{
    
    {"room", 0.8, 0.35, 5, 0.75, 0.30, 0.00, 0.00, 0.50, 0.15, 0.00, 16000.0},
    {"hall", 2.8, 0.65, 4, 0.70, 0.35, 0.00, 0.20, 0.40, 0.10, 0.00, 14000.0},
    {"galaxy", 12.0, 0.90, 3, 0.60, 0.50, 0.15, 0.70, 0.25, 0.05, 0.10, 12000.0},
    {"shimmer", 6.0, 0.70, 4, 0.65, 0.40, 0.60, 0.40, 0.30, 0.10, 0.00, 15000.0},
    {"lofi", 1.6, 0.45, 0, 0.55, 0.25, 0.00, 0.00, 0.70, 0.20, 0.35, 7000.0},
}}

kModMaxFraction

double pulp::signal::fdn::kModMaxFraction = 0.0035

inlineconstexpr

kModRateMaxHz

double pulp::signal::fdn::kModRateMaxHz = 1.50

inlineconstexpr

kModRateMinHz

double pulp::signal::fdn::kModRateMinHz = 0.10

inlineconstexpr

kModShrinkFloor

double pulp::signal::fdn::kModShrinkFloor = 0.25

inlineconstexpr

kModShrinkFullSeconds

double pulp::signal::fdn::kModShrinkFullSeconds = 2.0

inlineconstexpr

kModShrinkMinSeconds

double pulp::signal::fdn::kModShrinkMinSeconds = 20.0

inlineconstexpr

kModSineMix

double pulp::signal::fdn::kModSineMix = 0.6

inlineconstexpr

kModWalkMix

double pulp::signal::fdn::kModWalkMix = 0.4

inlineconstexpr

kNumChannels

int pulp::signal::fdn::kNumChannels = 16

inlineconstexpr

kNumEnsembleLfos

int pulp::signal::fdn::kNumEnsembleLfos = 6

inlineconstexpr

kNumEqBands

int pulp::signal::fdn::kNumEqBands = 10

inlineconstexpr

kNumModes

int pulp::signal::fdn::kNumModes = static_cast<int>(Mode::count)

inlineconstexpr

kNumParams

int pulp::signal::fdn::kNumParams = static_cast<int>(Param::count)

inlineconstexpr

kNumShimmerGrains

int pulp::signal::fdn::kNumShimmerGrains = 4

inlineconstexpr

kNumTankRates

int pulp::signal::fdn::kNumTankRates = static_cast<int>(kTankRates.size())

inlineconstexpr

kOscReanchorSamples

int pulp::signal::fdn::kOscReanchorSamples = 4096

inlineconstexpr

kParamSpecs

std::array<ParamSpec, kNumParams> pulp::signal::fdn::kParamSpecs

inlineconstexpr

Initial value:

= {{
    {"decay", 0.1, 60.0, 2.5, false},
    {"size", 0.0, 1.0, 0.5, false},
    {"predelay", 0.0, 250.0, 10.0, false},
    {"damp_hi", 0.0, 1.0, 0.4, false},
    {"damp_lo", 0.0, 1.0, 0.1, false},
    {"diffusion", 0.0, 1.0, 0.7, false},
    {"mod", 0.0, 1.0, 0.35, false},
    {"shimmer", 0.0, 1.0, 0.0, false},
    {"drive", 0.0, 1.0, 0.0, false},
    {"bloom", 0.0, 1.0, 0.0, false},
    {"width", 0.0, 1.0, 1.0, false},
    {"tank_rate", 0.0, 7.0, 1.0, true},
}}

kPostHadamardCeil

double pulp::signal::fdn::kPostHadamardCeil = 4.0

inlineconstexpr

kPreDiffusionBaseMs

double pulp::signal::fdn::kPreDiffusionBaseMs = 12.0

inlineconstexpr

kPreDiffusionG

double pulp::signal::fdn::kPreDiffusionG = 0.70

inlineconstexpr

kPreDiffusionStages

int pulp::signal::fdn::kPreDiffusionStages = 4

inlineconstexpr

kRateMakeupDb

std::array<double, 8> pulp::signal::fdn::kRateMakeupDb

inlineconstexpr

Initial value:

= {
    2.01, 1.42, 0.92, 0.35, 0.06, 0.00, 0.21, 0.26}

kRingStaggerSamples

std::size_t pulp::signal::fdn::kRingStaggerSamples = 37 * 16

inlineconstexpr

kSanityCeil

double pulp::signal::fdn::kSanityCeil = 10.0

inlineconstexpr

kShimmerGrainMaxMs

double pulp::signal::fdn::kShimmerGrainMaxMs = 60.0

inlineconstexpr

kShimmerGrainMinMs

double pulp::signal::fdn::kShimmerGrainMinMs = 40.0

inlineconstexpr

kShimmerMaxWeight

double pulp::signal::fdn::kShimmerMaxWeight = 0.6

inlineconstexpr

kShimmerToneHz

double pulp::signal::fdn::kShimmerToneHz = 8000.0

inlineconstexpr

kSizeScaleMax

double pulp::signal::fdn::kSizeScaleMax = 5.0 / 3.0

inlineconstexpr

kSizeScaleMin

double pulp::signal::fdn::kSizeScaleMin = 0.5

inlineconstexpr

kSmoothingMs

double pulp::signal::fdn::kSmoothingMs = 5.0

inlineconstexpr

kTankInputLpFraction

double pulp::signal::fdn::kTankInputLpFraction = 0.42

inlineconstexpr

kTankInputLpThresholdHz

double pulp::signal::fdn::kTankInputLpThresholdHz = 18000.0

inlineconstexpr

kTankRates

std::array<double, 8> pulp::signal::fdn::kTankRates

inlineconstexpr

Initial value:

= {
    16000.0, 20000.0, 24000.0, 32000.0, 44100.0, 48000.0, 64000.0, 96000.0}

kWalkReversion

double pulp::signal::fdn::kWalkReversion = 0.004

inlineconstexpr

kWalkStep

double pulp::signal::fdn::kWalkStep = 0.09

inlineconstexpr

kWetLimiterHeadroom

double pulp::signal::fdn::kWetLimiterHeadroom = 2.0

inlineconstexpr