The program, "From Dresden to Innsbruck (and Back)," features sacred music from the German-speaking lands that constitute the musical/historical legacy on which Mozart would ultimately draw. There are three motets (plus one beloved madrigal to the Alpine town of Innsbruck) by Heinrich Isaac, a 15th-16th-century composer whom many contemporaries considered the near-equal of the great Josquin Desprez; a double-choir Mass setting and a motet by the 16th-century German composer Hans Leo Hassler; and Heinrich Sch‹tz's German-language setting of the Magnificat.
Also on the program is one of the Tallis Scholars' signature pieces, and a work which we know for certain the child Mozart heard. Gregorio Allegri's Miserere mei, Deus, a setting of Psalm 51, was the exclusive property of the Sistine Chapel Choir, which used it as the finale of the very dramatic Tenebrae liturgy during Holy Week. (Candles were progressively extinguished throughout the service, and the Miserere was sung in darkness.) The Vatican had long threatened anathema for anyone who released a copy of Allegri's music to outsiders; young Wolfgang Amad_ heard the work in the Sistine Chapel and wrote it out from memory afterwards, panicking his father. (Mozart's manuscript of the Miserere has not, to anyone's knowledge, survived.)
The Miserere the Tallis Scholars sing will certainly not be what Mozart (or Allegri, for that matter) heard. The music as originally notated was falsobordone — basically a harmonized reciting tone, a simple series of chords which the choir used on successive verses of the Psalm; the Sistine singers would improvise embellishments to those chords on the spot. The version commonly known today, with its famous series of high Cs for soprano, was created and published in the 1930s with an English text; an edition in Latin was published and made famous in the 1950s by the great English choral conductor George Guest. Peter Phillips, founder and director of the Tallis Scholars, has prepared the edition used for this tour; soprano soloist Deborah Roberts, quite a queen of the high Cs herself, has provided some of her own embellishments.
The Tallis Scholars perform "From Dresden to Innsbruck (and Back)" on August 15 at the Ravinia Festival (www.ravnia.org), August 16 at Lincoln Center's Mostly Mozart Festival (www.lincolncenter.org) and August 17 at the Tanglewood Music Festival (www.tanglewood.org).