Heinrich Isaac

Career Summary

• centered in Florence during city's golden age;  court of Maximilian
• 1484 document refers to Isaac as receiving a payment in Innsbruck en route from Flanders to Florence at invitation of Lorenzo de'Medici, il Magnifico
• sang in cathedral choir, church of Santisima Annunziata in Florence;  tutored Lorenzo's children in music, including Giovanni, later Pope Leo X
• stayed until after Lorenzo's death in 1492; political climate forced him to leave
• accepted post as composer to Emperor Maximilian in 1497, an appointment which did not require his presence at court
• may have worked for periods in Innsbruck, at Augustinian monaster in Neustift, Constance, elsewhere
• was in Florence at regular intervals from 1499 on
• when Medici were restored to power in 1512, regained at least his former salary
• was released from service to Emperor in Vienna in 1515, who also granted him pension
• returned to Florence, died 2 years later
• no complete edition of his music, although one is in progress;  however, much of his music has been studied, especially secular
• Masses have not all been published
• except for motets in Choralis Constantinus, few are available in modern editions
• cosmopolitan approach:  French chanson, Flemish sacred polyphony, Italian carnival, German tenor lieder
• understood and mastered all of regional dialects which eventually fragmented international style

Mass

• Modern edition edited by Webern
• published long after Isaac's death:  3 volumes between 1550-55 by Hieronymus Formschneider of Nuremberg
• commissioned by diocese of Constance, but doubts remain on this
• completed by Ludwig Senfl, pupil of Isaac:  work unfinished at Isaac's death
• volumes differ in style and arrangement
• over 300 polyphonic settings of Propers for all Sundays; major feasts, saints' days:  100 liturgical occasions
• first composer since Leonin and Perotin to attempt task; only composer of Renaissance to do so except William Byrd
• summa of Netherlandish polyphony about 1500: comprehensive compendium of virtually all devices, manners, styles prevalent at the time;  illuminating as summary of ways in which cantus-firmus technique could be applied to new equal-voiced polyphony
• polyphonically set Introit, Alleluia or Tract, Sequence or Prosa and Communion; Offertory and Gradual left to be performed in Plainchant
• composed only one of Sequence double versicles
• 5 settings of Mass Ordinary appended to collection leave out phrases of text
• omitted portions of Sequences and Mass Ordinaries intended to be performed as plainsong; or relevant chant was arranged for solo organ
• for each Mass, polyphony alternates with plainsong or organ music:  alternatim
• book I:  fewer sequences-less appropriate for liturgical occasions included;  paraphrases chant in top voice; in later volumes he moved it to tenor or bass
• 2-6 voices, usually 4; grows slightly more complex and florid from one volume to another
• use of complex notation in book III:  summa of proportional practice; one of few sources in which difficult proportional signs explained by theorists are actually used
• Mass for Christmas Day: Introit
• begins with "classical" point of imitation in four parts; chant laid out in style which is identical in all four voices
• verse opens with imitation by duet; upper voice of each duet paraphrases chant
• Alleluia verse sounds less imitative because of full texture; however upper two voices of tutti do imitate each other;  superius paraphrases chant
• Alleluia verse begins with non-imitative duet in which top voice paraphrases chant
• Communion contrasts non-imitative counterpoint in upper two voices with canon in lower two

Motet

• sometimes places chant, in long notes or florid style similar to other voice, in only one part
• divides chant between two or more voices
• develops in imitation; combines with second borrowed melody

• comparable with Josquin's lamenting motets
• austere mournful beginning on open fifths, octaves; broadens into flowing mass
• fragment of canon over pedal point in appropriately dark low register: text painting

Secular Music

• association with Florence resulted in a handful of Italian songs:  declamatory chordal style
• boisterous carnival songs, lyrical ballate
• association with Maximilian:  German songs in 3-4 voices which follow in footsteps of his northern contemporaries Heinrich Finck and Paul Hofhaimer
• German songs state principal melody in tenor: counterpoint weaves around it
• neglected Burgundian chanson in favor of lively songs distinguished for their motivic interplay and rhythmic drive;  arrangements of popular tunes
• few rondeaux attributed to Isaac are recompositions of older songs:  J'ay pris amours
• used first few notes of borrowed melody as an ostinato, repeated at various pitches in lowest voice against superius
• elegant Burgundian melodies:  curve
• many secular pieces without text:  instrumental (Brown thinks that there may be text that has become lost)
• short compositions in imitative counterpoint; extended pieces in which single simple motive is elaborated with interplay (La la ho ho); 
• elaborate counterpoint supported by Cantus Firmus derived from solmization syllables (La mi la sol) or simple melodic formulae (Palle, palle: based on battle cry of Medici faction)