An interesting parallel has been made by J. B. Hutchings in his “The Baroque Concerto” (London 1961), between the Bolognese masters, who established the concerto-form, and the Orchestra of Mannheim in the second half of the XVIII century, who gave a crucial contribution to the symphony-form. Even if – according to the modern history of music standards and preconceptions –top rank composers cannot be found in both these two orchestras, amongst them dwelled the awareness, the wisdom and the hardihood of an Army of Generals, paraphrasing Charles Burney's quotation16.
Amongst the Petronian generals, Torelli is the composer who gave the most prominent impulse to the concerto-form. During the first years of employment in the musical chapel of San Petronio, under the chapel master Giovanni Paolo Colonna, Torelli distinguished himself not only as a player but also for his compositions, quickly becoming the composer in charge for most of the instrumental music that had to be performed by the musical chapel, as it is confirmed by his numerous instrumental works held in the Archive of San Petronio (more than 80) and by the salary increase of lire 5.12 that he received in 1688.
The instrumentation, the compositional expedients and structural forms adopted for the compositions that he wrote for San Petronio reflect the attention to the specific location for which they were intended. The church of San Petronio is one of the biggest in Europe, the fourth biggest in Italy: 132 metres long, 60 metres wide, 44.27 metres high, this peculiar indoor space presents several characteristics to be taken into account. The sound resonates in the interior with 12 seconds of reverberation delay, due to the massive dimensions of the space. The persistent resonance in the naves produces natural overtones, in such a way, for instance, that if two notes at a distance of a fifth are played, an audible major third will be generated in the nave, making the use of the Picardy third an acoustic necessity. Furthermore, there is a rapid decay of bass frequencies, which makes unavoidable the use of many more forces in the bass instruments and in the continuo sections in order to maintain audibility. Lastly, two different acoustic spaces can be distinguished in the interior: the choir and transept, situated in the middle of the horseshoe shape created by the balcony above where the musicians were located, from where the result of a musical performance is pretty clear - this was the space where the most prominent secular and religious authorities took place; and the naves, in which the sounds come across much more confused and mingled - this was the space occupied by the rest of the assembly. The instrumentation, the compositional expedients and structural forms adopted for the compositions that Torelli wrote for San Petronio reflect the attention to the specific location for which they were intended.
For this reason, a privileged instrument in the acoustic of this church is the trumpet, with its bright and distinct tone that stands out amongst the timbres of the string instruments and the organs. Compositions for the trumpet, to be performed in San Petronio, were written already in the years in which Maurizio Cazzati was the chapel master (1657-1671).
In the wake of this tradition, Giuseppe Torelli wrote several compositions for one, two, four trumpets and strings, adding also oboes and bassoons in the second period of his employment in the musical chapel (from 1701). Torelli adopted a musical form for these compositions which is not the traditional sonata da chiesa structure (4 movements: slow, fast, slow fast), still used in Bologna by Domenico Gabrielli or Giuseppe Jacchini. Torelli's trumpet compositions (indifferently labelled as Sonata, Sinfonia, Concerto) present a general pattern which can be considered the basis for most of the composer's orchestral works, and more specifically for his concertos. We can call this form 'abstract', since the structure of the movements is not related to dances, and it consists of three movements, in which the second one is multi-sectional. Marc Vanscheeuwijck described it in this way:
The central part of the composition only rarely includes a trumpet part: generally, it consists of a virtuoso solo section for one or two violins with scales and/or broken chords in fast tempo, symmetrically preceded and followed by a melodically and harmonically related tutti section. Often the form of this middle movement in three sections recalls the structure of a da capo-aria (ABA or ABA'). The first and final movements, always including trumpet(s), are most often set in a structure akin to the ritornello form17.
The fast external movements do not present a fixed contraposition of tutti ritornelli andsolo episodes according to a specific harmonic pattern (as Vivaldi, amongst the others, often did). Torelli, instead, made use of the so-called principle of alternation, a fundamental main feature in the vocal and instrumental repertoire in San Petronio. Widely applied by Franceschini, Colonna and Perti it consists in the contraposition of imitative and fugal counterpoint with passages in homophonic counterpoint. In his trumpet compositions, Torelli often subdivided the instrumental ensemble in concertino and concerto grande, providing a variety of dynamic contrasts and different timbre solutions.
It is problematic to draw a possible evolution in the setting used by Torelli during the years of activity in San Petronio, since most of the manuscripts held in the Archive of the church are not dated. It is clear, nevertheless, that Torelli dedicated himself to the experimentation of different setting solutions (varying the number of soloists from 1 up to 4), while establishing the above-mentioned structure as the compositional form.
Fig. 11 Leonardo Sconzani, in Le Insigna degli anziani del comune, miniature representing the presbytery of San Petronio during the solemn celebration of the Patron Saint, at the presence of the highest religious and municipal authorities; James III of England, Ireland and Scotland and his wife Clementina. 172215.
In the last two decades of the XVIII century Bologna became a sort of experimental musical laboratory where a new form was established for the instrumental concerto grosso, due to the fortunate and particular conditions that characterized that environment.
All the innovations introduced by Stradella were certainly very well known in the Bolognese environment too (were Stradella himself studied, during his youth): in 1681 he got in direct contact with the court of Modena in order to present his Il Trespolo Tutore there; he also received a commission for an Oratorio (Susanna) for which the libretto was written by the above-mentioned Court Secretary Giovanni Battista Giardini (unfortunately not finished due to the premature death of the composer – murdered in Genoa in 1682). Since the work of Stradella was held in great consideration in the Este court, after his death, the Duke Francesco II managed to buy a significant number of manuscripts from Stradella's nephews, promoting performances of his music during the following years with his court orchestra.
These facts prove how much the fervent Bolognese scene was keeping itself informed on the most recent trends and innovations. The cultural life was in constant motion thanks to a network of religious organizations, private societies and Accademie led and coordinated by the most important municipal institutions: San Petronio and the Accademia Filarmonica.
The musical chapel of San Petronio provided music for all the liturgical services of the church and the most important municipal festivities. Thanks to the enterprising chapel masters, the orchestra could count on important financial resources, allowing the possibility of hiring up to 120 musicians (between soloists, choir and orchestra) for the most solemn occasions, such as the Patron Saint day on the 4th of October or the Accademia Filarmonica's annual celebration in the church of San Giovanni in Monte on the day of Saint Anthony, the 17th of January.
Furthermore, in order to enter in the ranks of the orchestra, the musicians had to pass through a tough skimming procedure: becoming a member of the Accademia Filarmonica and being called as a supernumerary musician – which represented a sort of apprenticeship – was the usual path that the aspirants had to follow. In this way the Fabbriceria could choose the best candidate, once that a position in the orchestra would have become free. In fact, all of the musicians of San Petronio were considered to be virtuosi of their own instrument and most of them proved to be excellent composers, too. The Fabbriceria was aware of the excellent talents serving in the musical chapel and the consequent great demand for the Petronian musicians and their compositions, coming from the opera theatres and the ducal courts of the cities nearby. For this reason, and in order to keep a constant level of quality for the orchestra's performances, a major relevance was given to the presences and absences of the musicians, as it is shown from the payment registers in the Archive of San Petronio. The musicians had to submit a motivated request for leave of absence to the Fabbriceria and get their favourable permission: in case of frequent absences, not agreed beforehand by the Fabbriceri, the musician would lose his position.
Being able to have such a big ensemble at their disposal, performing on such a frequent basis, enabled the Bolognese composers to develop a stable orchestral praxis and appropriate, avant-garde musical forms for it. Therefore, after the activity of the Roman pioneers, the instrumental concerto found its consecration in Bologna.
