Listen to Concerto for Violoncello and Orchestra in A minor Op. 129: Langsam online. Concerto for Violoncello and Orchestra in A minor Op. 129: Langsam is an English language song and is sung by RTZ Symphony Orchestra, Josef Daniel and Valter Despalj - Violoncello. Concerto for Violoncello and Orchestra in A minor Op. 129: Langsam, from the album Hidden Classical Gems - The Complete Collection 50 Treasured Classics, was released in the year 2011. The duration of the song is 4:56. Download English songs online from JioSaavn.