download audio file javascript
var filename = url.substring(url.lastIndexOf("/") + 1).split("?")[0];
var xhr = new XMLHttpRequest();
xhr.responseType = 'blob';
xhr.onload = function() {
var a = document.createElement('a');
a.href = window.URL.createObjectURL(xhr.response);
a.download = filename;
a.style.display = 'none';
document.body.appendChild(a);
a.click();
delete a;
};
xhr.open('GET', url);
xhr.send();