During his 35 years, Mozart wrote 18 masses, including the famous, unfinished Requiem. Although 9 years and some 200 compositions separate the two works, the C-Minor Mass was Mozart's final mass before the Requiem. While both call for bassoons, trumpets, trombones, timpani, strings and organ, the Requiem emphasizes a more somber sonority with its clarinets. The C-Minor Mass favors flute, oboes and horns for a brighter, more versatile palette. In the choir, too, the Mass features a double chorus, meaning at times the four-part ensemble (soprano, alto, tenor and bass) can split into eight parts for added harmonic and textural complexity.
The C-Minor Mass was begun in celebration of the composer's marriage to Constanze Weber. The couple had their first child just months before the work's performance in Salzburg, and it is likely that Constanze was a soloist in its premiere. At the time, only the Kyrie and Gloria had been completed. That the work was not composed in response to a specific commission may also account for its unfinished status.
The opening Kyrie begins with soft, somber strings laying out a descending pattern before creeping back up to the opening C which accompanies the choir's forceful entrance. The choral parts enter in turn: soprano, alto, tenor and bass. The sopranos and tenors extend the C minor triad to an octave-and-a-half, creating a hollow chorale. The barest of melodic ingredients—a mere three notes are used in the chorus's three-bar opening phrase—combine to create a sound as if from a haunted planet. Mozart then immediately contrasts this with an elaborately chromatic development section that uses all twelve tones.
Having begged for mercy, the work suddenly shifts tone to exultation: C minor becomes C major. Gloria is proclaimed with a fanfare from the full choir and orchestra. The basses get to announce the theme this time, which works its way up from lowest to highest voices in a fugue-like setting. The rhythmic fanfare underscores in excelsis several times in possible tribute to the "Hallelujah" chorus from Messiah. Mozart gives his wife another chance to shine in the soprano solo Laudamus te succeeded by a rather unsettling key change into the brief adagio, Gratias. The following Domine features both soprano soloists in a dance-like duet. A striking moment comes near the end, when the two alternate with expressive high notes, almost as if the composer were pitting them against each other.
One could be forgiven for hearing the Qui tollis and mistaking it for Bach. Eight-part choral writing (featured frequently in Bach Passion settings) is underwritten by a severe, dotted rhythm (a hallmark of the Baroque style) throughout. The tenor and two soprano soloists deliver a refreshing change of pace with the flowing Quoniam. The voices make their way up the scale to cascade down again, one voice following the next in imitation. Having sung past and around each other for so long, it is arresting when the three voices find each other in unison just past the mid-point of the movement.
The fugue has always been a form in which composers have shown (and shone) their skill. Mozart demonstrates his mastery in the Cum Sancto Spiritu, in which the opening theme, after finding its way multiple times through all voices, is inverted and played upside down. Before he's finished, Mozart manages to play both the original and inverted themes simultaneously!
The Credo section of a mass says a mouthful. Here the choir works its way through the text alternately declaiming together and in echo. The soprano solo that follows, Et incarnatus est, rivals Mozart's most beautiful opera arias. The woodwind writing is exquisite, both in its interplay among the woodwinds and between winds and soloist. The Sanctus features the return of the double chorus. The orchestra provides a steady, somewhat menacing rhythmic underpinning slowly building to a climax that releases in the allegro Osanna. Next, Mozart finally lets all four soloists shine in the Benedictus, featuring florid passages in each voice. The choir returns for the final Osanna.
© 2008 Tyler S. Clark
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