documentation

packages/core/controls.mjs

@@ -430,6 +430,17 @@ export const { crush } = registerControl('crush');
  */
 export const { coarse } = registerControl('coarse');
 
+/**
+ * filter overdrive for supported filter types
+ *
+ * @name drive
+ * @param {number | Pattern} amount
+ * @example
+ * note("{f g g c d a a#}%16".sub(17)).s("supersaw").lpenv(8).lpf(150).lpq(.8).ftype('ladder').drive("<.5 4>")
+ *
+ */
+export const { drive } = registerControl('drive');
+
 /**
  * Allows you to set the output channels on the interface
  *
@@ -750,7 +761,7 @@ export const { bprelease, bpr } = registerControl('bprelease', 'bpr');
  * .sound('sawtooth')
  * .lpf(500)
  * .bpenv(4)
- * .ftype("12db 24db")
+ * .ftype("<ladder 12db 24db>")
  */
 export const { ftype } = registerControl('ftype');
 export const { fanchor } = registerControl('fanchor');

packages/superdough/helpers.mjs

@@ -103,13 +103,13 @@ export const getADSRValues = (params, curve = 'linear', defaultValues) => {
   return [Math.max(a ?? 0, envmin), Math.max(d ?? 0, envmin), Math.min(sustain, envmax), Math.max(r ?? 0, releaseMin)];
 };
 
-export function createFilter(context, type, frequency, Q, att, dec, sus, rel, fenv, start, end, fanchor, model) {
+export function createFilter(context, type, frequency, Q, att, dec, sus, rel, fenv, start, end, fanchor, model, drive) {
   const curve = 'exponential';
   const [attack, decay, sustain, release] = getADSRValues([att, dec, sus, rel], curve, [0.005, 0.14, 0, 0.1]);
   let filter;
   let frequencyParam;
   if (model === 'ladder') {
-    filter = getWorklet(context, 'ladder-processor', { frequency, q: Q, drive: 1 });
+    filter = getWorklet(context, 'ladder-processor', { frequency, q: Q, drive });
     frequencyParam = filter.parameters.get('frequency');
   } else {
     filter = context.createBiquadFilter();

packages/superdough/superdough.mjs

@@ -290,6 +290,7 @@ export const superdough = async (value, t, hapDuration) => {
     // filters
     ftype = '12db',
     fanchor = 0.5,
+    drive = 0.69,
     // low pass
     cutoff,
     lpenv,
@@ -297,7 +298,7 @@ export const superdough = async (value, t, hapDuration) => {
     lpdecay,
     lpsustain,
     lprelease,
-    resonance = 1,
+    resonance = 0.5,
     // high pass
     hpenv,
     hcutoff,
@@ -412,6 +413,7 @@ export const superdough = async (value, t, hapDuration) => {
         t + hapDuration,
         fanchor,
         ftype,
+        drive,
       );
     chain.push(lp());
     if (ftype === '24db') {

packages/superdough/worklets.mjs

@@ -1,6 +1,6 @@
 // coarse, crush, and shape processors adapted from dktr0's webdirt: https://github.com/dktr0/WebDirt/blob/5ce3d698362c54d6e1b68acc47eb2955ac62c793/dist/AudioWorklets.js
 // LICENSE GNU General Public License v3.0 see https://github.com/dktr0/WebDirt/blob/main/LICENSE
-
+import { clamp } from './util.mjs';
 const blockSize = 128;
 class CoarseProcessor extends AudioWorkletProcessor {
   static get parameterDescriptors() {
@@ -111,13 +111,13 @@ function fast_tanh(x) {
   return (x * (27.0 + x2)) / (27.0 + 9.0 * x2);
 }
 const _PI = 3.14159265359;
-
+//adapted from https://github.com/TheBouteillacBear/webaudioworklet-wasm?tab=MIT-1-ov-file
 class LadderProcessor extends AudioWorkletProcessor {
   static get parameterDescriptors() {
     return [
       { name: 'frequency', defaultValue: 500 },
       { name: 'q', defaultValue: 1 },
-      { name: 'drive', defaultValue: 1 },
+      { name: 'drive', defaultValue: 0.69 },
     ];
   }
 
@@ -145,13 +145,14 @@ class LadderProcessor extends AudioWorkletProcessor {
     this.started = hasInput;
 
     const resonance = parameters.q[0];
-    const drive = parameters.drive[0] * 2;
+    const drive = clamp(Math.exp(parameters.drive[0]), 0.1, 2000);
     let cutoff = parameters.frequency[0];
     cutoff = (cutoff * 2 * _PI) / sampleRate;
     cutoff = cutoff > 1 ? 1 : cutoff;
 
-    const k = resonance * 4;
-    const makeupgain = 1 / drive;
+    const k = Math.min(8, resonance * 2);
+    //               drive makeup  * resonance volume loss makeup
+    const makeupgain = (1 / drive) * Math.min(1.75, 1 + k);
 
     for (let n = 0; n < blockSize; n++) {
       for (let i = 0; i < input.length; i++) {