Audio compressor

src/constants.js

@@ -128,4 +128,4 @@ export const FONT_WIDTH = 3;
 export const FONT_HEIGHT = 5;
 
 export const SOUND_MUSIC_VOLUME = 0.3;
-export const SOUND_SFX_VOLUME = 0.05;
+export const SOUND_SFX_VOLUME = 0.1;

src/sound.js

@@ -2,14 +2,18 @@ import {SOUND_MUSIC_VOLUME, SOUND_SFX_VOLUME} from './constants.js';
 
 // @ts-ignore
 export const audio = new (window.AudioContext || window.webkitAudioContext)();
+export const volume = createGain(1);
+volume.connect(audio.destination);
 
-export const music = audio.createGain(audio);
+export const music = createCompressor();
-music.gain.setValueAtTime(SOUND_MUSIC_VOLUME, audio.currentTime);
+export const musicGain = createGain(SOUND_MUSIC_VOLUME);
-music.connect(audio.destination);
+music.connect(musicGain);
+musicGain.connect(volume);
 
-export const sfx = audio.createGain(audio);
+export const sfx = createCompressor();
-sfx.gain.setValueAtTime(SOUND_SFX_VOLUME, audio.currentTime);
+export const sfxGain = createGain(SOUND_SFX_VOLUME);
-sfx.connect(audio.destination);
+sfx.connect(sfxGain);
+sfxGain.connect(volume);
 
 export async function createAudioLoop(src) {
   const file = await fetch(src);
@@ -30,6 +34,22 @@ export function createOsc(type='triangle') {
   return osc;
 }
 
+export function createGain(amount) {
+  const gain = audio.createGain();
+  gain.gain.setValueAtTime(amount, audio.currentTime);
+  return gain;
+}
+
+export function createCompressor() {
+  let compressor = audio.createDynamicsCompressor();
+  compressor.threshold.setValueAtTime(-30, audio.currentTime);
+  compressor.knee.setValueAtTime(40, audio.currentTime);
+  compressor.ratio.setValueAtTime(12, audio.currentTime);
+  compressor.attack.setValueAtTime(0, audio.currentTime);
+  compressor.release.setValueAtTime(0.25, audio.currentTime);
+  return compressor;
+}
+
 export function playTickSound() {
   const osc = createOsc('triangle');
   osc.frequency.setValueAtTime(440, audio.currentTime);