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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

  <h1>Audio player with tempo adjustment</h1>
  <p>Maintains pitch while slowing an MP3 down.<br>For beginner guitarists, like myself, to practice chord progressions at a managable pace.</p>
  <div class=group>
    <h2>Audio source (.mp3)</h2>

    <div class=url>
      <label class=url_label for=url_input><span>Address</span></label>
      <input id=url_input class=url_input type=url value="https://websemantics.uk/pens/audio-tempo-change-fixed-pitch/media/hard-days-night.mp3">


    <div class=upload>
      <label class=upload_label for=upload_input><span>Upload</span></label>
      <input id=upload_input class=upload_input type=file accept="audio/*">

  <div class=group>
    <div class=player>
      <h3 class=player_display></h3>
      <audio class=player_audio controls>
        <track id=player-chords kind=captions srclang=en>

    <div class=tempo>
      <label class=tempo_label for=tempo_input>Tempo</label>
      <input class=tempo_input id=tempo_input type=range value=0.825 min=0.5 max=1 step=0.025>
      <span class=tempo_display></span>

<footer class=myStuff><style>.myStuff{z-index:10;font-weight:100;color:#777;font-size:16px;position:fixed;width:100vw;left:0;bottom:0;margin:0;background-color:hsla(269,19%,20%,.9);padding:.125em;line-height:1.5;text-align:center}.myStuff_lnk,.myStuff_lnk:visited{text-decoration-skip: ink;color:hsla(211,100%,72%,1);text-decoration-color:hsla(211,100%,72%,.5);transition:all .3s ease-out;white-space:nowrap}.myStuff_lnk:focus,.myStuff_lnk:hover{color:#fff;text-decoration-color:currentcolor}</style><a class=myStuff_lnk target=linkedin title="[LinkedIn - new window]" href="https://www.linkedin.com/in/mikefoskett">Mike Foskett</a> &nbsp; <a class=myStuff_lnk target=popularpens title="[new window]" href="https://codepen.io/2kool2/pens/popular/?grid_type=list#">Popular pens</a> &nbsp; <a class=myStuff_lnk target=latestpens title="[new window]" href="https://codepen.io/2kool2/pens/public/?grid_type=list#">Latest pens</a> &nbsp; <a class=myStuff_lnk target=webSemantics title="[new window]" href="https://websemantics.uk/">webSemantics</a></footer>
              body {
  --spacing: .75rem;
  font-family: sans-serif;
  line-height: 1.5;
  text-align: center;
  margin: .75rem;
  padding-bottom: 2rem;
  color: hsl(269,19%,30%);
  background-color: hsla(32,100%,85%,.35);
  background-image: url("data:image/svg+xml;charset=utf8,%3Csvg width='100%25' xmlns='http://www.w3.org/2000/svg'%3E%3Cdefs%3E%3Cfilter id='a'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.4'/%3E%3C/filter%3E%3C/defs%3E%3C!-- %3Cpath filter='url(%23a)' opacity='.3' d='M0 0h1200v256H0z'/%3E--%3E%3Crect filter='url(%23a)' opacity='.3' width='100%25' height='100%25'/%3E%3C/svg%3E");
@media (min-width: 48em) {
  body {--spacing: 1rem;}
body * {box-sizing: border-box;}
h1, h2, h3 {font-weight:100;}
h1 {margin: 1em 0 .5em;}
.group {
  border: 1px solid #fff;
  background-color: rgba(255,255,255,.25);
  padding: .5rem 1rem;
  margin: 1rem auto;

.url {
  display: flex;
  width: 100%;
  margin: 1rem auto;
[class*="_label"] {
  position: relative;
  white-space: nowrap;
  margin-right: .5em;
  min-width: 4em;
[class*="_label"] > span {
  display: block;
  position: relative;
  top: 50%;
  transform: translatey(-50%);
[class*="_input"] {
  display: inline-block;
  line-height: 1;
  width: 100%;
  margin: 0;
  padding: .25rem .5rem;
  font: inherit;
  border: 1px solid #fff;
  background-color: rgba(255,255,255,.5);

.upload {
  display: flex;
  width: 100%;
  margin: 1rem auto;

.player_audio {
  width: 100%;
.player_display {
  font-size: 1.25rem;
.tempo {
  display: flex;
  width: 100%;
  margin: 1rem auto;
.tempo_display {
  font-weight: 700;
  min-width: 3em;
  margin-left: .5em;
const player = document.querySelector('.player_audio');
const playerDisplay = document.querySelector('.player_display');

const changeTempo = function () {
  player.playbackRate = tempoInput.value;
  tempoDisplay.textContent = tempoInput.value;

const changeSongURL = function (e) {
  player.src = urlInput.value;
  let filename = player.src.split('\\').pop().split('/').pop();
  playerDisplay.textContent = filename;

const changeSongFile = function (e) {
  const target = e.currentTarget;
  const file = target.files[0];
  let reader;

  if (target.files && file) {
    reader = new FileReader();
    reader.onload = function (e) {
      player.setAttribute('src', e.target.result);
      playerDisplay.textContent = file.name;
      // player.play(); // auto play on load

// Get the song from:
const urlInput = document.getElementById('url_input');
urlInput.addEventListener("change", changeSongURL, false);

// Or upload an MP3:
const uploadInput = document.getElementById('upload_input');
uploadInput.addEventListener('change', changeSongFile, false);

// Playback tempo 
const tempoInput = document.getElementById('tempo_input');
tempoInput.addEventListener("change", changeTempo, false);
const tempoDisplay = document.querySelector('.tempo_display');
tempoDisplay.textContent = tempoInput.value;

// Chords from:
const vtt = document.getElementById('url_input').value.replace('.mp3', '.vtt');
const player_chords = document.getElementById('player-chords');

player_chords.src = vtt;
// player.src = urlInput.value;
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