Merge pull request #713 from Bubobubobubobubo/noise

Add 'white', 'pink' and 'brown' oscillators + refactor synth

packages/core/controls.mjs

@@ -655,6 +655,15 @@ const generic_params = [
    * .vib("<.5 1 2 4 8 16>:12")
    */
   [['vib', 'vibmod'], 'vibrato', 'v'],
+  /**
+   * Adds pink noise to the mix
+   *
+   * @name noise
+   * @param {number | Pattern} wet wet amount
+   * @example
+   * sound("<white pink brown>/2")
+   */
+  ['noise'],
   /**
    * Sets the vibrato depth in semitones. Only has an effect if `vibrato` | `vib` | `v` is is also set
    *
@@ -1153,7 +1162,7 @@ const generic_params = [
   ['pitchJump'],
   ['pitchJumpTime'],
   ['lfo', 'repeatTime'],
-  ['noise'],
+  ['znoise'], // noise on the frequency or as bubo calls it "frequency fog" :)
   ['zmod'],
   ['zcrush'], // like crush but scaled differently
   ['zdelay'],

packages/superdough/helpers.mjs

@@ -112,3 +112,25 @@ export function createFilter(
 
   return filter;
 }
+
+// stays 1 until .5, then fades out
+let wetfade = (d) => (d < 0.5 ? 1 : 1 - (d - 0.5) / 0.5);
+
+// mix together dry and wet nodes. 0 = only dry 1 = only wet
+// still not too sure about how this could be used more generally...
+export function drywet(dry, wet, wetAmount = 0) {
+  const ac = getAudioContext();
+  if (!wetAmount) {
+    return dry;
+  }
+  let dry_gain = ac.createGain();
+  let wet_gain = ac.createGain();
+  dry.connect(dry_gain);
+  wet.connect(wet_gain);
+  dry_gain.gain.value = wetfade(wetAmount);
+  wet_gain.gain.value = wetfade(1 - wetAmount);
+  let mix = ac.createGain();
+  dry_gain.connect(mix);
+  wet_gain.connect(mix);
+  return mix;
+}

packages/superdough/noise.mjs

@@ -0,0 +1,63 @@
+import { drywet } from './helpers.mjs';
+import { getAudioContext } from './superdough.mjs';
+
+let noiseCache = {};
+
+// lazy generates noise buffers and keeps them forever
+function getNoiseBuffer(type) {
+  const ac = getAudioContext();
+  if (noiseCache[type]) {
+    return noiseCache[type];
+  }
+  const bufferSize = 2 * ac.sampleRate;
+  const noiseBuffer = ac.createBuffer(1, bufferSize, ac.sampleRate);
+  const output = noiseBuffer.getChannelData(0);
+  let lastOut = 0;
+  let b0, b1, b2, b3, b4, b5, b6;
+  b0 = b1 = b2 = b3 = b4 = b5 = b6 = 0.0;
+
+  for (let i = 0; i < bufferSize; i++) {
+    if (type === 'white') {
+      output[i] = Math.random() * 2 - 1;
+    } else if (type === 'brown') {
+      let white = Math.random() * 2 - 1;
+      output[i] = (lastOut + 0.02 * white) / 1.02;
+      lastOut = output[i];
+    } else if (type === 'pink') {
+      let white = Math.random() * 2 - 1;
+      b0 = 0.99886 * b0 + white * 0.0555179;
+      b1 = 0.99332 * b1 + white * 0.0750759;
+      b2 = 0.969 * b2 + white * 0.153852;
+      b3 = 0.8665 * b3 + white * 0.3104856;
+      b4 = 0.55 * b4 + white * 0.5329522;
+      b5 = -0.7616 * b5 - white * 0.016898;
+      output[i] = b0 + b1 + b2 + b3 + b4 + b5 + b6 + white * 0.5362;
+      output[i] *= 0.11;
+      b6 = white * 0.115926;
+    }
+  }
+  noiseCache[type] = noiseBuffer;
+  return noiseBuffer;
+}
+
+// expects one of noises as type
+export function getNoiseOscillator(type = 'white', t) {
+  const ac = getAudioContext();
+  const o = ac.createBufferSource();
+  o.buffer = getNoiseBuffer(type);
+  o.loop = true;
+  o.start(t);
+  return {
+    node: o,
+    stop: (time) => o.stop(time),
+  };
+}
+
+export function getNoiseMix(inputNode, wet, t) {
+  const noiseOscillator = getNoiseOscillator('pink', t);
+  const noiseMix = drywet(inputNode, noiseOscillator.node, wet);
+  return {
+    node: noiseMix,
+    stop: (time) => noiseOscillator?.stop(time),
+  };
+}

packages/superdough/synth.mjs

@@ -1,6 +1,7 @@
 import { midiToFreq, noteToMidi } from './util.mjs';
 import { registerSound, getAudioContext } from './superdough.mjs';
 import { gainNode, getEnvelope, getExpEnvelope } from './helpers.mjs';
+import { getNoiseMix, getNoiseOscillator } from './noise.mjs';
 
 const mod = (freq, range = 1, type = 'sine') => {
   const ctx = getAudioContext();
@@ -20,75 +21,26 @@ const fm = (osc, harmonicityRatio, modulationIndex, wave = 'sine') => {
   return mod(modfreq, modgain, wave);
 };
 
+const waveforms = ['sine', 'square', 'triangle', 'sawtooth'];
+const noises = ['pink', 'white', 'brown'];
+
 export function registerSynthSounds() {
-  ['sine', 'square', 'triangle', 'sawtooth'].forEach((wave) => {
+  [...waveforms, ...noises].forEach((s) => {
     registerSound(
-      wave,
+      s,
       (t, value, onended) => {
         // destructure adsr here, because the default should be different for synths and samples
-        let {
+        let { attack = 0.001, decay = 0.05, sustain = 0.6, release = 0.01 } = value;
-          attack = 0.001,
-          decay = 0.05,
-          sustain = 0.6,
-          release = 0.01,
-          fmh: fmHarmonicity = 1,
-          fmi: fmModulationIndex,
-          fmenv: fmEnvelopeType = 'lin',
-          fmattack: fmAttack,
-          fmdecay: fmDecay,
-          fmsustain: fmSustain,
-          fmrelease: fmRelease,
-          fmvelocity: fmVelocity,
-          fmwave: fmWaveform = 'sine',
-          vib = 0,
-          vibmod = 0.5,
-        } = value;
-        let { n, note, freq } = value;
-        // with synths, n and note are the same thing
-        note = note || 36;
-        if (typeof note === 'string') {
-          note = noteToMidi(note); // e.g. c3 => 48
-        }
-        // get frequency
-        if (!freq && typeof note === 'number') {
-          freq = midiToFreq(note); // + 48);
-        }
-        // maybe pull out the above frequency resolution?? (there is also getFrequency but it has no default)
-        // make oscillator
-        const { node: o, stop } = getOscillator({
-          t,
-          s: wave,
-          freq,
-          vib,
-          vibmod,
-          partials: n,
-        });
 
-        // FM + FM envelope
+        let sound;
-        let stopFm, fmEnvelope;
+        if (waveforms.includes(s)) {
-        if (fmModulationIndex) {
+          sound = getOscillator(s, t, value);
-          const { node: modulator, stop } = fm(o, fmHarmonicity, fmModulationIndex, fmWaveform);
+        } else {
-          if (![fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity].find((v) => v !== undefined)) {
+          sound = getNoiseOscillator(s, t);
-            // no envelope by default
-            modulator.connect(o.frequency);
-          } else {
-            fmAttack = fmAttack ?? 0.001;
-            fmDecay = fmDecay ?? 0.001;
-            fmSustain = fmSustain ?? 1;
-            fmRelease = fmRelease ?? 0.001;
-            fmVelocity = fmVelocity ?? 1;
-            fmEnvelope = getEnvelope(fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity, t);
-            if (fmEnvelopeType === 'exp') {
-              fmEnvelope = getExpEnvelope(fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity, t);
-              fmEnvelope.node.maxValue = fmModulationIndex * 2;
-              fmEnvelope.node.minValue = 0.00001;
-            }
-            modulator.connect(fmEnvelope.node);
-            fmEnvelope.node.connect(o.frequency);
-          }
-          stopFm = stop;
         }
 
+        let { node: o, stop, triggerRelease } = sound;
+
         // turn down
         const g = gainNode(0.3);
 
@@ -104,10 +56,9 @@ export function registerSynthSounds() {
           node: o.connect(g).connect(envelope),
           stop: (releaseTime) => {
             releaseEnvelope(releaseTime);
-            fmEnvelope?.stop(releaseTime);
+            triggerRelease?.(releaseTime);
             let end = releaseTime + release;
             stop(end);
-            stopFm?.(end);
           },
         };
       },
@@ -146,36 +97,108 @@ export function waveformN(partials, type) {
   return osc;
 }
 
-export function getOscillator({ s, freq, t, vib, vibmod, partials }) {
+// expects one of waveforms as s
-  // Make oscillator with partial count
+export function getOscillator(
+  s,
+  t,
+  {
+    n: partials,
+    note,
+    freq,
+    vib = 0,
+    vibmod = 0.5,
+    noise = 0,
+    // fm
+    fmh: fmHarmonicity = 1,
+    fmi: fmModulationIndex,
+    fmenv: fmEnvelopeType = 'lin',
+    fmattack: fmAttack,
+    fmdecay: fmDecay,
+    fmsustain: fmSustain,
+    fmrelease: fmRelease,
+    fmvelocity: fmVelocity,
+    fmwave: fmWaveform = 'sine',
+  },
+) {
+  let ac = getAudioContext();
   let o;
+  // If no partials are given, use stock waveforms
   if (!partials || s === 'sine') {
     o = getAudioContext().createOscillator();
     o.type = s || 'triangle';
-  } else {
+  }
+  // generate custom waveform if partials are given
+  else {
     o = waveformN(partials, s);
   }
+
+  // get frequency from note...
+  note = note || 36;
+  if (typeof note === 'string') {
+    note = noteToMidi(note); // e.g. c3 => 48
+  }
+  // get frequency
+  if (!freq && typeof note === 'number') {
+    freq = midiToFreq(note); // + 48);
+  }
+
+  // set frequency
   o.frequency.value = Number(freq);
   o.start(t);
 
+  // FM
+  let stopFm, fmEnvelope;
+  if (fmModulationIndex) {
+    const { node: modulator, stop } = fm(o, fmHarmonicity, fmModulationIndex, fmWaveform);
+    if (![fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity].find((v) => v !== undefined)) {
+      // no envelope by default
+      modulator.connect(o.frequency);
+    } else {
+      fmAttack = fmAttack ?? 0.001;
+      fmDecay = fmDecay ?? 0.001;
+      fmSustain = fmSustain ?? 1;
+      fmRelease = fmRelease ?? 0.001;
+      fmVelocity = fmVelocity ?? 1;
+      fmEnvelope = getEnvelope(fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity, t);
+      if (fmEnvelopeType === 'exp') {
+        fmEnvelope = getExpEnvelope(fmAttack, fmDecay, fmSustain, fmRelease, fmVelocity, t);
+        fmEnvelope.node.maxValue = fmModulationIndex * 2;
+        fmEnvelope.node.minValue = 0.00001;
+      }
+      modulator.connect(fmEnvelope.node);
+      fmEnvelope.node.connect(o.frequency);
+    }
+    stopFm = stop;
+  }
+
   // Additional oscillator for vibrato effect
-  let vibrato_oscillator;
+  let vibratoOscillator;
   if (vib > 0) {
-    vibrato_oscillator = getAudioContext().createOscillator();
+    vibratoOscillator = getAudioContext().createOscillator();
-    vibrato_oscillator.frequency.value = vib;
+    vibratoOscillator.frequency.value = vib;
     const gain = getAudioContext().createGain();
     // Vibmod is the amount of vibrato, in semitones
     gain.gain.value = vibmod * 100;
-    vibrato_oscillator.connect(gain);
+    vibratoOscillator.connect(gain);
     gain.connect(o.detune);
-    vibrato_oscillator.start(t);
+    vibratoOscillator.start(t);
+  }
+
+  let noiseMix;
+  if (noise) {
+    noiseMix = getNoiseMix(o, noise, t);
   }
 
   return {
-    node: o,
+    node: noiseMix?.node || o,
     stop: (time) => {
-      vibrato_oscillator?.stop(time);
+      vibratoOscillator?.stop(time);
+      noiseMix?.stop(time);
+      stopFm?.(time);
       o.stop(time);
     },
+    triggerRelease: (time) => {
+      fmEnvelope?.stop(time);
+    },
   };
 }

packages/superdough/zzfx.mjs

@@ -20,7 +20,7 @@ export const getZZFX = (value, t) => {
     pitchJump = 0,
     pitchJumpTime = 0,
     lfo = 0,
-    noise = 0,
+    znoise = 0,
     zmod = 0,
     zcrush = 0,
     zdelay = 0,
@@ -54,7 +54,7 @@ export const getZZFX = (value, t) => {
     pitchJump,
     pitchJumpTime,
     lfo,
-    noise,
+    znoise,
     zmod,
     zcrush,
     zdelay,

test/__snapshots__/examples.test.mjs.snap

@@ -2959,6 +2959,15 @@ exports[`runs examples > example "never" example index 0 1`] = `
 ]
 `;
 
+exports[`runs examples > example "noise" example index 0 1`] = `
+[
+  "[ (0/1 → 1/1) ⇝ 2/1 | s:white ]",
+  "[ 0/1 ⇜ (1/1 → 2/1) | s:white ]",
+  "[ (2/1 → 3/1) ⇝ 4/1 | s:pink ]",
+  "[ 2/1 ⇜ (3/1 → 4/1) | s:pink ]",
+]
+`;
+
 exports[`runs examples > example "note" example index 0 1`] = `
 [
   "[ 0/1 → 1/4 | note:c ]",

website/src/pages/learn/synths.mdx

@@ -23,6 +23,25 @@ The basic waveforms are `sine`, `sawtooth`, `square` and `triangle`, which can b
 
 If you don't set a `sound` but a `note` the default value for `sound` is `triangle`!
 
+## Noise
+
+You can also use noise as a source by setting the waveform to: `white`, `pink` or `brown`. These are different
+flavours of noise, here written from hard to soft.
+
+<MiniRepl client:idle tune={`sound("<white pink brown>/2").scope()`} />
+
+Here's a more musical example of how to use noise for hihats:
+
+<MiniRepl
+  client:idle
+  tune={`sound("bd*2,<white pink brown>*8")
+.decay(.04).sustain(0).scope()`}
+/>
+
+Some amount of pink noise can also be added to any oscillator by using the `noise` paremeter:
+
+<MiniRepl client:idle tune={`note("c3").noise("<0.1 0.25 0.5>").scope()`} />
+
 ### Additive Synthesis
 
 To tame the harsh sound of the basic waveforms, we can set the `n` control to limit the overtones of the waveform: