harga, buku, biaya, kursus, sekolah, musik, Yamaha, music, school, media, sosial, situs, resmi, 2020, 2021, kelas, fantasi, pendaftaran, anak, usia, 2 tahun, per bulan, wonderland, drum, guitar, piano, electone, saxophone, keyboard, review, jenis, keunggulan, vokal