commit e7008d731e8ed05a8cb077b0fbedd9776c32def6
parent 0ebc4fdb6a3ef18797bc536740e5b586079ef9df
Author: Matt Demanett <matt@demanett.net>
Date: Sun, 14 Oct 2018 19:25:41 -0400
Fix LMTR to be a limiter (non-distorting) instead of a clipper (distorting). Create CLPR to be a clipper. #22
Diffstat:
11 files changed, 332 insertions(+), 4 deletions(-)
diff --git a/README.md b/README.md
@@ -278,9 +278,17 @@ The various controls and ports work as follows:
Several of the settings can take fairly extreme values (e.g. OUT GAIN); this allows the module to be used as a distortion effect.
+#### CLPR
+
+CLPR is a compact (6HP) [clipper](https://en.wikipedia.org/wiki/Clipping_%28audio%29). Its controls behave the same as the corresponding controls on PRESSOR.
+
+In contrast to LMTR, CLPR chops a signal at a voltage threshold corresponding to the selected amplitude; this distorts the signal.
+
#### LMTR
-LMTR is a compact (6HP) hard [limiter](https://en.wikipedia.org/wiki/Dynamic_range_compression) or clipper. Its controls behave the same as the corresponding controls on PRESSOR.
+LMTR is a compact (6HP) [limiter](https://en.wikipedia.org/wiki/Dynamic_range_compression). Its controls behave the same as the corresponding controls on PRESSOR.
+
+In contrast to CLPR, LMTR does not distort the signal (or not much); it just reduces the amplitude of the signal to keep it below the threshold.
#### NSGT
diff --git a/doc/www/effects.png b/doc/www/effects.png
Binary files differ.
diff --git a/doc/www/modules2.png b/doc/www/modules2.png
Binary files differ.
diff --git a/res-src/Clpr-src.svg b/res-src/Clpr-src.svg
@@ -0,0 +1,144 @@
+<svg
+ version="1.1"
+ xmlns="http://www.w3.org/2000/svg"
+ xmlns:xlink="http://www.w3.org/1999/xlink"
+ width="90"
+ height="380"
+ viewBox="0 0 90 380"
+>
+ <style>
+ text {
+ fill: #333;
+ font-family: 'Roboto', sans-serif;
+ font-weight: bold;
+ }
+ text.title {
+ font-family: 'Comfortaa', sans-serif;
+ font-weight: normal;
+ }
+ text.brand {
+ font-family: 'Audiowide', sans-serif;
+ font-weight: bold;
+ }
+ </style>
+
+ <defs>
+ <symbol id="knob38" viewBox="0 0 38px 38px">
+ <g transform="translate(19 19)">
+ <polyline points="-5,0 5,0" stroke-width="1" stroke="#00f" />
+ <polyline points="0,-5 0,5" stroke-width="1" stroke="#00f" />
+ <circle cx="0" cy="0" r="18.5" stroke-width="1" stroke="#00f" fill="none" />
+ </g>
+ </symbol>
+
+ <symbol id="knobguide-threshold38" viewBox="0 0 70px 70px">
+ <g transform="translate(35 35)">
+ <text font-size="6.0pt" transform="rotate(-240) translate(25 0) rotate(240) translate(-10 2.5)">-24</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-210) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-180) translate(25 0) rotate(180) translate(-10 2.5)">-18</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-150) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-120) translate(25 0) rotate(120) translate(-10 2.5)">-12</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-90) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-60) translate(25 0) rotate(60) translate(-2.3 2.5)">-6</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-30) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(0) translate(25 0) rotate(0) translate(-2.3 2.5)">0</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(30) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(60) translate(25 0) rotate(-60) translate(-2.3 2.5)">6</text>
+ <text font-size="6.0pt" transform="rotate(90) translate(29 0) rotate(-90) translate(-4.7 2.2)">dB</text>
+ </g>
+ </symbol>
+
+ <symbol id="knobguide-outputgain38" viewBox="0 0 70px 70px">
+ <g transform="translate(35 35)">
+ <text font-size="6.0pt" transform="rotate(-240) translate(25 0) rotate(240) translate(-4 2.5)">0</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-202.5) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-165) translate(25 0) rotate(165) translate(-3.5 2.5)">6</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-127.5) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-90) translate(25 0) rotate(90) translate(-5 2.5)">12</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(-52.5) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(-15) translate(25 0) rotate(15) translate(-2 2.5)">18</text>
+ <polyline points="0,0 3,0" stroke-width="0.3" stroke="#333" transform="rotate(22.5) translate(21 0)" />
+ <text font-size="6.0pt" transform="rotate(60) translate(25 0) rotate(-60) translate(-1 2.5)">24</text>
+ <text font-size="6.0pt" transform="rotate(90) translate(29 0) rotate(-90) translate(-4.7 2.2)">dB</text>
+ </g>
+ </symbol>
+
+ <symbol id="switch" viewBox="0 0 14px 24px">
+ <rect width="14px" height="24px" stroke-width="1" stroke="#000" fill="#ddd" />
+ <rect width="14px" height="12px" stroke-width="0" fill="#000" />
+ </symbol>
+
+ <symbol id="input" viewBox="0 0 24px 24px">
+ <g transform="translate(12 12)">
+ <circle cx="0" cy="0" r="5" stroke-width="1" stroke="#0f0" fill="#0f0" />
+ <circle cx="0" cy="0" r="10.5" stroke-width="3" stroke="#0f0" fill="none" />
+ </g>
+ </symbol>
+
+ <symbol id="output" viewBox="0 0 24px 24px">
+ <g transform="translate(12 12)">
+ <circle cx="0" cy="0" r="5" stroke-width="1" stroke="#f00" fill="#f00" />
+ <circle cx="0" cy="0" r="10.5" stroke-width="3" stroke="#f00" fill="none" />
+ </g>
+ </symbol>
+ </defs>
+
+ <rect width="100%" height="100%" fill="#ddd" />
+ <polyline points="1,1 89,1 89,379 1,379 1,1" stroke="#e4e4e4" stroke-width="0.5" fill="none" />
+ <polyline points="0.5,0.5 89.5,0.5 89.5,379.5 0.5,379.5 0.5,0.5" stroke="#ebebeb" stroke-width="0.8" fill="none" />
+ <polyline points="0,0 90,0 90,380 0,380 0,0" stroke="#f2f2f2" stroke-width="1" fill="none" />
+
+ <text class="title" x="38" y="17" font-size="9pt" letter-spacing="3px">CLPR</text>
+ <g transform="translate(5.5 374)">
+ <text class="brand" font-size="6.5pt" letter-spacing="2px">BOGAUDIO</text>
+ <rect width="1.5" height="2" fill="#ddd" transform="translate(21 -4)" />
+ </g>
+
+ <!-- <polyline points="0,0 0,380" stroke="#0f0" stroke-width="1" fill="none" transform="translate(45 0)" /> -->
+ <!-- <rect width="90" height="15" fill="#0f0" transform="translate(0 18)" /> -->
+ <!-- <rect width="90" height="15" fill="#0f0" transform="translate(0 102)" /> -->
+ <!-- <rect width="90" height="7" fill="#0f0" transform="translate(0 185)" /> -->
+ <!-- <rect width="90" height="7" fill="#0f0" transform="translate(0 232)" /> -->
+
+ <g transform="translate(0 40)">
+ <text font-size="8pt" letter-spacing="2px" transform="translate(8 0)">THRESHOLD</text>
+ <use id="THRESHOLD_PARAM" xlink:href="#knob38" transform="translate(26 12)" />
+ <use xlink:href="#knobguide-threshold38" transform="translate(10 -4)" />
+ </g>
+
+ <g transform="translate(0 122)">
+ <text font-size="8pt" letter-spacing="2px" transform="translate(15.5 0)">OUT GAIN</text>
+ <use id="OUTPUT_GAIN_PARAM" xlink:href="#knob38" transform="translate(26 12)" />
+ <use xlink:href="#knobguide-outputgain38" transform="translate(10 -4)" />
+ </g>
+
+ <g transform="translate(40 198)">
+ <text font-size="5pt" letter-spacing="2px" transform="translate(-8 25.5) rotate(270)">KNEE</text>
+ <text font-size="5pt" letter-spacing="2px" transform="translate(-4 -1)">SOFT</text>
+ <use id="KNEE_PARAM" xlink:href="#switch" transform="translate(0 2)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(-5 34)">HARD</text>
+ </g>
+
+ <g transform="translate(11 240)">
+ <g transform="translate(0 0)">
+ <rect width="68" height="10" fill="#fafafa" transform="translate(0 66)" />
+ <rect width="68" height="73" rx="5" fill="#fafafa" />
+ <use id="LEFT_INPUT" xlink:href="#input" transform="translate(5 4)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(15.5 36)">L</text>
+ <use id="RIGHT_INPUT" xlink:href="#input" transform="translate(39 4)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(49 36)">R</text>
+ <use id="THRESHOLD_INPUT" xlink:href="#input" transform="translate(5 40)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(5.5 72)">TRSH</text>
+ <use id="OUTPUT_GAIN_INPUT" xlink:href="#input" transform="translate(39 40)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(42 72)">OGN</text>
+ </g>
+ <g transform="translate(0 79)">
+ <rect width="68" height="10" fill="#bbb" transform="translate(0 -3)" />
+ <rect width="68" height="37" rx="5" fill="#bbb" />
+ <use id="LEFT_OUTPUT" xlink:href="#output" transform="translate(5 1)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(15.5 33)">L</text>
+ <use id="RIGHT_OUTPUT" xlink:href="#output" transform="translate(39 1)" />
+ <text font-size="5pt" letter-spacing="2px" transform="translate(49 33)">R</text>
+ </g>
+ </g>
+</svg>
diff --git a/res/Clpr.svg b/res/Clpr.svg
Binary files differ.
diff --git a/src/Clpr.cpp b/src/Clpr.cpp
@@ -0,0 +1,95 @@
+
+#include "Clpr.hpp"
+
+void Clpr::onReset() {
+ _modulationStep = modulationSteps;
+}
+
+void Clpr::step() {
+ if (!(outputs[LEFT_OUTPUT].active || outputs[RIGHT_OUTPUT].active)) {
+ return;
+ }
+
+ ++_modulationStep;
+ if (_modulationStep >= modulationSteps) {
+ _modulationStep = 0;
+
+ _thresholdDb = params[THRESHOLD_PARAM].value;
+ if (inputs[THRESHOLD_INPUT].active) {
+ _thresholdDb *= clamp(inputs[THRESHOLD_INPUT].value / 10.0f, 0.0f, 1.0f);
+ }
+ _thresholdDb *= 30.0f;
+ _thresholdDb -= 24.0f;
+
+ float outGain = params[OUTPUT_GAIN_PARAM].value;
+ if (inputs[OUTPUT_GAIN_INPUT].active) {
+ outGain = clamp(outGain + inputs[OUTPUT_GAIN_INPUT].value / 5.0f, 0.0f, 1.0f);
+ }
+ outGain *= 24.0f;
+ if (_outGain != outGain) {
+ _outGain = outGain;
+ _outLevel = decibelsToAmplitude(_outGain);
+ }
+
+ _softKnee = params[KNEE_PARAM].value > 0.97f;
+ }
+
+ float leftInput = inputs[LEFT_INPUT].value;
+ float rightInput = inputs[RIGHT_INPUT].value;
+ float env = abs(leftInput + rightInput);
+ float detectorDb = amplitudeToDecibels(env / 5.0f);
+ float compressionDb = _compressor.compressionDb(detectorDb, _thresholdDb, Compressor::maxEffectiveRatio, _softKnee);
+ _amplifier.setLevel(-compressionDb);
+ if (outputs[LEFT_OUTPUT].active) {
+ outputs[LEFT_OUTPUT].value = _saturator.next(_amplifier.next(leftInput) * _outLevel);
+ }
+ if (outputs[RIGHT_OUTPUT].active) {
+ outputs[RIGHT_OUTPUT].value = _saturator.next(_amplifier.next(rightInput) * _outLevel);
+ }
+}
+
+struct ClprWidget : ModuleWidget {
+ static constexpr int hp = 6;
+
+ ClprWidget(Clpr* module) : ModuleWidget(module) {
+ box.size = Vec(RACK_GRID_WIDTH * hp, RACK_GRID_HEIGHT);
+
+ {
+ SVGPanel *panel = new SVGPanel();
+ panel->box.size = box.size;
+ panel->setBackground(SVG::load(assetPlugin(plugin, "res/Clpr.svg")));
+ addChild(panel);
+ }
+
+ addChild(Widget::create<ScrewSilver>(Vec(0, 0)));
+ addChild(Widget::create<ScrewSilver>(Vec(box.size.x - 15, 365)));
+
+ // generated by svg_widgets.rb
+ auto thresholdParamPosition = Vec(26.0, 52.0);
+ auto outputGainParamPosition = Vec(26.0, 134.0);
+ auto kneeParamPosition = Vec(39.5, 199.5);
+
+ auto leftInputPosition = Vec(16.0, 244.0);
+ auto rightInputPosition = Vec(50.0, 244.0);
+ auto thresholdInputPosition = Vec(16.0, 280.0);
+ auto outputGainInputPosition = Vec(50.0, 280.0);
+
+ auto leftOutputPosition = Vec(16.0, 320.0);
+ auto rightOutputPosition = Vec(50.0, 320.0);
+ // end generated by svg_widgets.rb
+
+ addParam(ParamWidget::create<Knob38>(thresholdParamPosition, module, Clpr::THRESHOLD_PARAM, 0.0, 1.0, 0.8));
+ addParam(ParamWidget::create<Knob38>(outputGainParamPosition, module, Clpr::OUTPUT_GAIN_PARAM, 0.0, 1.0, 0.0));
+ addParam(ParamWidget::create<SliderSwitch2State14>(kneeParamPosition, module, Clpr::KNEE_PARAM, 0.95, 1.0, 0.0));
+
+ addInput(Port::create<Port24>(leftInputPosition, Port::INPUT, module, Clpr::LEFT_INPUT));
+ addInput(Port::create<Port24>(rightInputPosition, Port::INPUT, module, Clpr::RIGHT_INPUT));
+ addInput(Port::create<Port24>(thresholdInputPosition, Port::INPUT, module, Clpr::THRESHOLD_INPUT));
+ addInput(Port::create<Port24>(outputGainInputPosition, Port::INPUT, module, Clpr::OUTPUT_GAIN_INPUT));
+
+ addOutput(Port::create<Port24>(leftOutputPosition, Port::OUTPUT, module, Clpr::LEFT_OUTPUT));
+ addOutput(Port::create<Port24>(rightOutputPosition, Port::OUTPUT, module, Clpr::RIGHT_OUTPUT));
+ }
+};
+
+Model* modelClpr = createModel<Clpr, ClprWidget>("Bogaudio-Clpr", "CLPR", "clipper", DYNAMICS_TAG, DISTORTION_TAG);
diff --git a/src/Clpr.hpp b/src/Clpr.hpp
@@ -0,0 +1,57 @@
+#pragma once
+
+#include "bogaudio.hpp"
+#include "dsp/signal.hpp"
+
+using namespace bogaudio::dsp;
+
+extern Model* modelClpr;
+
+namespace bogaudio {
+
+struct Clpr : Module {
+ enum ParamsIds {
+ THRESHOLD_PARAM,
+ OUTPUT_GAIN_PARAM,
+ KNEE_PARAM,
+ NUM_PARAMS
+ };
+
+ enum InputsIds {
+ LEFT_INPUT,
+ RIGHT_INPUT,
+ THRESHOLD_INPUT,
+ OUTPUT_GAIN_INPUT,
+ NUM_INPUTS
+ };
+
+ enum OutputsIds {
+ LEFT_OUTPUT,
+ RIGHT_OUTPUT,
+ NUM_OUTPUTS
+ };
+
+ enum LightsIds {
+ NUM_LIGHTS
+ };
+
+ const int modulationSteps = 100;
+ int _modulationStep = 0;
+ float _thresholdDb = 0.0f;
+ float _outGain = -1.0f;
+ float _outLevel = 0.0f;
+ bool _softKnee = true;
+
+ Compressor _compressor;
+ Amplifier _amplifier;
+ Saturator _saturator;
+
+ Clpr() : Module(NUM_PARAMS, NUM_INPUTS, NUM_OUTPUTS, NUM_LIGHTS) {
+ onReset();
+ }
+
+ void onReset() override;
+ void step() override;
+};
+
+} // namespace bogaudio
diff --git a/src/Lmtr.cpp b/src/Lmtr.cpp
@@ -5,6 +5,14 @@ void Lmtr::onReset() {
_modulationStep = modulationSteps;
}
+void Lmtr::onSampleRateChange() {
+ float sampleRate = engineGetSampleRate();
+ _detector.setSampleRate(sampleRate);
+ _attackSL.setParams(sampleRate, 150.0f);
+ _releaseSL.setParams(sampleRate, 600.0f);
+ _modulationStep = modulationSteps;
+}
+
void Lmtr::step() {
if (!(outputs[LEFT_OUTPUT].active || outputs[RIGHT_OUTPUT].active)) {
return;
@@ -36,7 +44,15 @@ void Lmtr::step() {
float leftInput = inputs[LEFT_INPUT].value;
float rightInput = inputs[RIGHT_INPUT].value;
- float env = abs(leftInput + rightInput);
+ float env = _detector.next(leftInput + rightInput);
+ if (env > _lastEnv) {
+ env = _attackSL.next(env, _lastEnv);
+ }
+ else {
+ env = _releaseSL.next(env, _lastEnv);
+ }
+ _lastEnv = env;
+
float detectorDb = amplitudeToDecibels(env / 5.0f);
float compressionDb = _compressor.compressionDb(detectorDb, _thresholdDb, Compressor::maxEffectiveRatio, _softKnee);
_amplifier.setLevel(-compressionDb);
@@ -92,4 +108,4 @@ struct LmtrWidget : ModuleWidget {
}
};
-Model* modelLmtr = createModel<Lmtr, LmtrWidget>("Bogaudio-Lmtr", "LMTR", "limiter/clipper", DYNAMICS_TAG, DISTORTION_TAG, EFFECT_TAG);
+Model* modelLmtr = createModel<Lmtr, LmtrWidget>("Bogaudio-Lmtr", "LMTR", "limiter", DYNAMICS_TAG);
diff --git a/src/Lmtr.hpp b/src/Lmtr.hpp
@@ -41,16 +41,22 @@ struct Lmtr : Module {
float _outGain = -1.0f;
float _outLevel = 0.0f;
bool _softKnee = true;
+ float _lastEnv = 0.0f;
+ SlewLimiter _attackSL;
+ SlewLimiter _releaseSL;
+ RootMeanSquare _detector;
Compressor _compressor;
Amplifier _amplifier;
Saturator _saturator;
Lmtr() : Module(NUM_PARAMS, NUM_INPUTS, NUM_OUTPUTS, NUM_LIGHTS) {
onReset();
+ onSampleRateChange();
}
void onReset() override;
+ void onSampleRateChange() override;
void step() override;
};
diff --git a/src/Pressor.cpp b/src/Pressor.cpp
@@ -243,4 +243,4 @@ struct PressorWidget : ModuleWidget {
}
};
-Model* modelPressor = createModel<Pressor, PressorWidget>("Bogaudio-Pressor", "Pressor", "stereo compressor", COMPRESSOR_TAG, DYNAMICS_TAG, EFFECT_TAG);
+Model* modelPressor = createModel<Pressor, PressorWidget>("Bogaudio-Pressor", "Pressor", "stereo compressor", COMPRESSOR_TAG, DYNAMICS_TAG);
diff --git a/src/bogaudio.cpp b/src/bogaudio.cpp
@@ -7,6 +7,7 @@
#include "AMRM.hpp"
#include "Analyzer.hpp"
#include "Bool.hpp"
+#include "Clpr.hpp"
#include "Cmp.hpp"
#include "CVD.hpp"
#include "DADSRH.hpp"
@@ -91,6 +92,7 @@ void init(rack::Plugin *p) {
p->addModel(modelAMRM);
p->addModel(modelPressor);
+ p->addModel(modelClpr);
p->addModel(modelLmtr);
p->addModel(modelNsgt);
