Vivaldi spent 37 years as the director of music at the Ospedale della Pieta, one of four schools in Venice for illegitimate, orphaned and deserted youngsters. The schools were attached to hospitals or charitable hostels, and their students were educated and maintained mainly at the state’s expense. The boys were apprenticed out to Venetian merchants and tradesmen to prepare them to become self-supporting. The girls, on the other hand, were cloistered like nuns and trained in music mainly as a way of attracting eligible young men for marriage.

The standards of music education at Vivaldi’s school were particularly high. The schools’ academic costs were heavily subsidized by the proceeds of regular Sunday concerts by the Ospedale’s orchestra and choir, usually but not always performing behind screens to protect the girls’ modesty. Under Vivaldi’s direction, these concerts became the talk of Venice, and no foreign visitor left the city without having attended a Vivaldi performance. In the words of one English visitor:

The girls sing like angels, play the violin, flute, organ, oboe, cello, bassoon – in short no instrument is large enough to frighten them. The performances are entirely their own and each concert is composed of about forty girls. I swear nothing is more charming than to see a young and pretty nun, dressed in white, a sprig of pomegranate blossom behind one ear, leading the orchestra and beating time with all the grace and precision imaginable.

For the concerts Vivaldi wrote some 500 concertos for various solo instruments, or combinations of solo instruments, and string orchestra. About one-half of them were for violin – hardly surprising considering that Vivaldi was a celebrated violinist. The rest included works for bassoon, cello, oboe, flute, viola d’amore, recorder and mandolin.

In addition, Vivaldi wrote three concertos for "flautino" and orchestra, including the one we hear this evening. Since the term "flautino" was not generally used in Vivaldi’s day, scholars have speculated ever since about what instrument Vivaldi had in mind. The leading candidates are the small sopranino recorder and the flageolet, an end-blown flute, but the former is usually preferred since Vivaldi specifically designated the flageolet when he used it.

At any rate, later in the 18^th century the transverse flute replaced both the recorder and the flageolet in general use, and a new edition of RV 443 was published for the piccolo, a member of the flute family. That is the version that we hear this evening.

In his instrumental concertos, Vivaldi perfected the form of what would become the Baroque instrumental concerto. First of all, he standardized the use of three movements in a fast-slow-fast pattern. Second, he developed the ritornello ("little return") form, in which the full body of instruments, known as the tutti, alternates with the solo instrument (or group of instruments) in presenting, repeating and developing the main thematic material. These juxtapositions of tutti refrains and solo passages opened new possibilities for virtuoso display by solo instrumentalists as well bold shifts into other keys.

In RV 443, Vivaldi adopted the ritornello for the fast first and third movements, and made the slow intervening movement as important as the other two.

The first movement, in C major, opens energetically with a ritornello for the main body of instruments, leading to an incredible display of agility by the soloist. The movement continues with considerable rhythmic drive, including further demanding solo episodes.

The slow movement, largo, is a slow singing aria in E minor to which the soloist, in the style of the day, was expected to add embellishments. The music is in the swaying, lilting rhythm of the siciliana, a folk dance that originated in Sicily and became a favorite with Baroque composers.

The third movement, allegro molto, restores both the C major key and the ritornello format. In the contrasting episodes, the soloist indulges in trills, arpeggios and rapid triplets, interrupted by brief passages for the tutti to give the soloist a chance for breath.

On May 11, 1747, the palace of Prussian King Frederick the Great at Potsdam issued the following press release, which was picked up by newspapers in Berlin, Frankfurt, Hamburg, Leipzig and Magdeburg:

Last Sunday the famous Kapellmeister from Leipzig, Mr. Bach, arrived with the intention to have the pleasure of hearing the excellent Royal music there. In the evening, at about the time when the regular chamber music in the Royal apartments usually begins, His Majesty was informed that Kapellmeister Bach had arrived at Potsdam and was waiting in His Majesty’s antechamber for His Majesty’s most gracious permission to listen to the music. His August self immediately gave orders that Bach be admitted, and went, at his entrance to the forte-piano, condescending also to play, in His Most August Person and without any preparation, a theme for the Kapellmeister Bach to expand into a fugue.

This was done so happily by the aforementioned Kapellmeister that not only His Majesty was pleased to show his satisfaction thereat, but also all those present were seized with astonishment. Mr. Bach found the theme propounded to him so exceedingly beautiful that he intends to set it down on paper as a regular fugue and have it engraved on copper...

In large measure, Frederick, an accomplished flutist and himself a composer, had invited Bach to Potsdam because of Bach’s reputation as a composer and improviser. But the king’s motivations were also political. In November, 1745, in the course of a war against Saxony, his troops had occupied Leipzig for a year, upsetting the city’s social and economic life. After the Prussian withdrawal, the Russian ambassador to Prussia, an admirer of Bach, persuaded the king to invite Leipzig’s most famous musician to Potsdam as a peace offering. The details were then worked out by Bach’s oldest son, Carl Philipp Emanuel, who had recently become music director in Halle in Prussian territory.

Accordingly, on May 7, Frederick spotted Bach’s name in the guest list for his evening concert of chamber music. "Gentleman," the king said, "old Bach has come," and he invited Bach to try out the palace’s collection of keyboard instruments. Then came the challenge to elaborate the Royal Theme into a fugue, although, according to Bach’s son Wilhelm Friedemann, who accompanied his father, the idea was proposed by Bach rather than by the king.

On his return to Leipzig in mid-May, Bach set to work to fulfill his promise of writing out his elaboration of the king’s theme. But the project grew to two fugues for the keyboard; a trio sonata for flute, violin and thorough bass; and 10 canons (a concentrated form of counterpoint). Bach himself entitled the complete work a Musical Offering.

The entire packet was delivered to the king with a flowery dedication dated July 7. The project had been expanded, the dedication stated, "to work out this right Royal theme more fully. . . to glorify, if only in a small point, the fame of a Monarch whose greatness and power, as in all the sciences of war and peace, so especially in music, everyone must admire and revere."

There is no record of royal gratitude for the work or even of its performance at Potsdam. But Bach himself ordered a print run of 200 copies, absorbed all the costs, distributed half of the copies at no charge to his friends, and sold the rest for one thaler per copy (about $72 in today’s currency). This price was his usual fee for playing at weddings and funerals and, in this case, netted him a small profit.

Today, the fugues and canons of the Musical Offering are mainly of academic interest – they are too complex for performance. The trio sonata, on the other hand, is considered one of Bach’s finest chamber works. With the flute part written specifically for Frederick, the sonata blends Bach’s mastery of contrapuntal writing with the more melodic and harmonically varied musical language favored by the younger composers at the Potsdam court.

The trio sonata is in four movements, with the Royal Theme taking a different form in each movement. In the opening largo, it is merely suggested. In the following allegro, it is used as a cantus firmus – that is, as a sustained "foundation tune" for a contrapuntal structure above it. In the third movement, andante, the theme is broken into shorter motives. In the closing allegro, the theme is the subject of a dance-like fugue.

The term "trio sonata" was the most common chamber-music designation during the Baroque period (roughly 1600 to 1750). A trio sonata was not a trio in the later sense of three instruments of equal importance. To the contrary, it originally called for four performers of unequal prominence playing three music lines – two featured instruments and an accompaniment consisting of a keyboard continuo to fill in the harmony and a cello or viola da gamba to reinforce the bass. Eventually, as the technical and tonal resources of the harpsichord were developed, the viola da gamba or cello was dispensed with, but the harpsichord continued in its continuo role.

The Argentine tango is a style of song and dance music rather than a specific dance or dance rhythm. It originated in the poor slum areas outside Buenos Aires in the late 19th century and has since remained the most popular Argentine song and dance style. While it comes in many varieties, its common characteristics are syncopated rhythmic patterns within a 2/4 meter, abrupt rhythmic and dynamic contrasts, and an accompaniment pattern in which all beats are sharply accented and occasionally interrupted by sudden pauses.

Traditionally, the dance is for couples in tight embrace and is characterized by almost violent movement. When sung, the lyrics reflect the origin of the tango among the urban poor -- pessimistic, fatalistic and often intensely negative in tone. The original performance groups were solo voice with guitar accompaniment, and trios with violin, flute, and guitar or bandoneón (a small accordion of German original but a favorite instrument in Argentina).

In recent years, the leading figure in the composition of tangos has been Astor Piazzolla, who was born in Mar del Plata, not far from Buenos Aires, but brought up in New York. Piazzolla learned the tango style and the bandoneón at an early age, but broadened his musical education to include study with Alberto Ginastera, Argentine’s leading classical composer. He also went to France to study with Nadia Boulanger, the great Paris teacher whose other pupils included Aaron Copland, Walter Piston, Virgil Thomson, and Roy Harris.

With this enrichment, Piazzolla introduced what became known as nuevo tango, absorbing into the traditional style such diverse influences as jazz, the dissonance of contemporary classical composition, and even Italian opera. He also added a harp and percussion instruments to the traditional tango orchestra and introduced the electric guitar into smaller ensembles. At the same time, he maintained the tango’s roots in the working-class dance halls and water-front nightclubs of Buenos Aires.

In addition to his own ensemble, Quinteto Tango Nuevo, Piazzolla experimented in adapting the tango to other instrumental media. Thus, he composed for solo bandoneón and symphony orchestra, string quartet, solo piano, solo guitar and guitar duet, and various other instrumental combinations.

This evening we hear three Piazzolla tangos arranged for flute, cello and piano by Pablo Zinger, a Uruguay-born pianist and conductor, now living in New York City. As an associate of Piazzolla, Zinger was influential in the development of the nuevo tango style and its continuation after Piazzolla’s death.

Libertango: Composed in 1954 after Piazzolla had returned from Paris to Buenos Aires, this was one of the earliest demonstrations of the composer’s nuevo tango style. "I was determined more than ever before," he said, "to treat the tango as absolute music. While based on the melodic, harmonic and above all, the rhythmical qualities of the tango, it is free from the socially defined context of its origins at the beginning of this century." Originally a duet for guitar and piano, it is one of Piazzolla’s most popular pieces in various arrangements, one of which is a well-known recording by cellist Yo Yo Ma.

Milonga in Re: A milonga is an Argentine place or event where the tango is danced, and by extension the music itself; re is D major. Piazzolla originally composed this piece as a duet for violin or cello and piano, and dedicated it to the French jazz violinist Stéphane Grapelli, whom he had met in Paris. The piece features a slow, introspective solo for the violincellist over a more moving piano part, with steadily increasing intensity.

La Muerte del Angel (The Death of the Angel): This is the climactic piece Piazzolla provided for his incidental music for a 1962 play by Alberto Rodriguez Muñoz in which an angel heals the spirits of the residents of a shabby Buenos Aires neighborhood. The angel is killed in a knife fight, but is then resurrected.

Piazzolla composed the piece originally for bandoneón, violin, piano and acoustic and electric bass; he then used it in two suites of Angel-related music and performed it independently. It begins as a three-voice fugue, based on a fast, jagged theme passed dissonantly among the instruments. It is interrupted by a contrasting central section simultaneously sentimental and unsettled. The fugue theme returns, but is no longer treated contrapuntally, ending in exciting string glissandi.

"I’ve now finished three movements of a new piano quartet, and the finale will be ready in a few days. As I expected, it came easily, and the melodies just surged upon me. Thanks Be to God!"

The quartet opens with a question-and-answer theme to take advantage of the contrast in sonorities between the piano and the strings. The strings, in unison, proclaim a muscular four-measure motive, and the piano gives a bantering, almost frivolous, reply. There is a contrasting second theme in the unexpected key of G major, but the two elements of the main theme dominate the development.

The recapitulation skips the first theme entirely, but the theme returns to open the coda. The coda has an ingenious touch – a quiet meditative version of the main theme played tremolando by the violin and viola, supported by isolated piano chords and plucked notes in the cello.