Listen to Waltz Op.12 (Grieg) online. Waltz Op.12 (Grieg) is an Instrumental language song and is sung by Music for Dog's Ears, Dog Music and Sleeping Music For Dogs. Waltz Op.12 (Grieg), from the album Dog Music: Classical Piano Music For Dogs, Music For Pets and Dog Sleeping Music, Vol. 2, was released in the year 2018. The duration of the song is 2:13. Download Instrumental songs online from JioSaavn.