PHP
<?php
$lg=$_GET['language'];
$voice=$_GET['voice'];
$text=$_GET['text'];
$lgs = ['vn' => 'vi-VN','en' => 'en-US'];
$voices=["A","B","C","D"];
$data = json_decode(file_get_contents('https://freetts.com/Home/PlayAudio?Language='.$lgs[$lg].'&Voice='.$lgs[$lg].'-Standard-'.$voices[$voice].'&type=0&TextMessage='.urlencode($text)),true);
if($data["msg"]=="True") {
header('Content-Type: audio/mpeg');
echo file_get_contents("https://freetts.com/audio/".$data["id"]);
} else {
echo "Lỗi Cmnr!";
}