https://doujinblog.org/160826-mirai-%e3%83%8f%e3%83%8a%e3%83%92%e3%83%a1%ef%bc%8a%e3%82%a2%e3%83%96%e3%82%bd%e3%83%aa%e3%83%a5%e3%83%bc%e3%83%88%ef%bc%81-%e5%88%9d%e5%9b%9e%e9%99%90%e5%ae%9a%e7%89%88-vocal-track-bat/