Listen to Allegretto from the Quartet #21 in D Major, K. 575 online. Allegretto from the Quartet #21 in D Major, K. 575 is an English language song and is sung by Eder Quartet. Allegretto from the Quartet #21 in D Major, K. 575, from the album Music for the Mozart Effect: Volume 3, Music for Creativity & Imagination, was released in the year 1997. The duration of the song is 7:42. Download English songs online from JioSaavn.