Corelli: Trio Sonata in D, 4th Movement

Background Information:

• Arcangelo Corelli (1653-1713): one of the most influential composers of the late Baroque period.
• 'Trio Sonata' was composed in 1689.
• Context of piece: - part of a set of 12 Church Sonatas (Sonatas de Chiesa) to be played either in church or at a sacred concert. - typically consisted of 4 movements (usually slow, fast, slow, fast). - broadly contrapuntal in style. 
• 'Trio Sonata': - is in D major. - has four movements (grave, allegro, adagio, allegro). - there are no melodic links between the movements. 

Performance Circumstances:

• Number of performers: 4 performers, 2 violins, 1 violone and an organ.
• Violins are broadly equal partners: - share a similar tessitura. - often imitate each other at the unison. - cross parts. - exchange ideas. 
• Violone is a low pitched bowed string instrument: similar range to violin. 
• Continuo is played by organ: improvising harmonies above given figured bass. 

Texture:

• Three part imitative counterpoint.
• Opening sounds fugal, with the 1st violin stating subject, 2nd stating answer (in the dominant). 
• Monophony in bars 1-2.
• 2 part in parallel thirds in bar 3.
• Stretto imitation at the start of the B section (parts enter with shorter intervals than before). 
• Polarised texture: e.g bars 11-12 (where violins play close together whilst violone is widely spaced apart). 
• Inverted pedal at the end of A section, bars 15-18. 
• Parallel tenths between violin II and violone in bars 8-9. 
• Violone drops out of imitation and plays more distinct bass line in section B.
• All 3 parts drop down an octave in final 3 bars. 

Structure: 

• Binary form (each section repeated: AABB).
• A section (bars 1-19): starts in D major and modulates to dominant A major.
• B section (bars 20-43): -begins in dominant with same melody material as A section, but inverted. -modulates through various related keys before returning to tonic at end. -bars 41-43 can be seen as codetta.

Phrase Structure and Keys:

• Bars 1-2: 2 bar fugal subject in D major (tonic). 
• Bars 3-4: 2 bar fugal answer in A major (dominant).
• Bars 11-19: entries in A major.
• Bars 23-42: entries on dominant, tonic, relative B minor, relative subdominant of B minor (E minor), dominant again, tonic, relative subdominant of tonic (G major), before finally returning to tonic. 

Harmony

• Entirely diatonic. 
• Largely consonant, using mostly root and first inversion chords. 
• Dissonance through carefully prepared suspension, usually resolving downwards by step (eg. bars 15-18 in violone). 
• Frequent cadences which define phrase structure (eg. I-V in bar 4) and also changes of key (eg. V-I in bars 10-11). 
• Perfect cadences defining changes of key are masculine (ending on strong beats, eg. in bar 11), whereas perfect cadences to define phrase structure are feminine (ending on weak beats, e.g. in bar 4).
• Functional harmony evident in cycle of fifths in bars 32-35, and pedal points heralding ends of sections (eg. bars 15-18). 

Melody:

• Monothematic, all melodies are derived from opening 3 note motif (which is based on a rising 3rd). 
• Motifs are developed through: - sequence with added passing notes (second half of bar 1). - inversion (bar 20). - juxtaposition of opening motif and its inversion in rising sequence (bar 11 etc). 
• Occasionally an octave leap (eg. 1st violin in bar 7) will break the characteristic descending sequences. 

Rhythm & Metre:

• Written in style of a gigue, a lively dance in compound time. 
• Phrasing in dotted crotchets emphasises strong rhythm. 
• Corelli varies metre through: - violone entering halfway through a bar (eg. bar 6). - syncopation in first violin part in B section. - hemiolas in B section.