The Symphony No. 6 in D minor, Op. 104, was a work of long gestation completed by Jean Sibelius in 1923. Although the score does not contain a key attribution, the symphony is usually described as being in D minor; much of it is in fact in the (modern) Dorian mode. A typical performance lasts about 25 minutes. The composer called the work "cold spring water" in opposition to many contemporary "cocktails"—a reference to the modernist gestures in post-war music. The symphony was premiered by the Helsinki Philharmonic Orchestra, conducted by the composer, on 19 February 1923 and had other performances under his direction in the following months.