Tenshi, Ei-chan, and Shiratori all attend Kawagoe Academy. One day, they get pulled into the orbit of former conductor Haruo. He drags them into his newly founded boys choir where they suddenly find themselves performing a song in front of an audience!

What's wrong? You can hear 
the note from the piano, can't you?
ما الخطب؟ يمكنكم سماع لحن البيانو، أليس كذلك؟
Was war das denn?
Ihr habt den Ton doch gehört, oder?
¿Qué pasa?
¿No oyeron el piano?
¿Qué pasa?
¿No habéis oído el piano?
Bah alors ?
Vous entendez le piano, non ?
Che vi prende?
O que foi?
Vocês ouviram o piano, não?
Ну и чего вы? 
Слышали же ноту, разве нет?