Recorder.setupDownload = function(blob, filename){
    var url = (window.URL || window.webkitURL).createObjectURL(blob);
    var link = document.getElementById("save");
    link.href = url;
    link.download = filename || 'output.wav';

    var data = new FormData();
    data.append("data", blob, link.download);
    var xhr = (window.XMLHttpRequest) ? new XMLHttpRequest() : new activeXObject("Microsoft.XMLHTTP");
    xhr.open( 'post', '/save.php', true );
    xhr.send(data);

}

<?php
if(!empty($_POST['data'])){

        $data = $_POST['data'];
        $fname = mktime() . ".wav";//generates random name

        $file = fopen("audio/" .$fname, 'w');//creates new file
        fwrite($file, $data);
        fclose($file);
}
?>

<a id="save" href="blob:http://doamin.ru/a0982168-5ae2-4823-9e03-6a160821aee9" download="myRecording00.wav">

<a id="save" href="blob:http://doamin.ru/a0982168-5ae2-4823-9e03-6a160821aee9" download="myRecording00.wav">

  Recorder.setupDownload = function(blob, filename){
    var url = (window.URL || window.webkitURL).createObjectURL(blob);
    var link = document.getElementById("save");
    link.href = url;
    link.download = filename || 'output.wav';

    // alert(blob);
    // alert(JSON.stringify(blob));
    // console.log(blob);

     var reader = new window.FileReader();
       reader.readAsDataURL(blob);
       reader.onloadend = function() {
               base64data = reader.result;
               console.log(base64data);
                                         }
    var data = new FormData();
    data.append("data", reader.base64data );
    var xhr = (window.XMLHttpRequest) ? new XMLHttpRequest() : new activeXObject("Microsoft.XMLHTTP");
    xhr.open( 'post', '/save.php', true );
    xhr.send(data);

  }