Ricardo Muti's decision to revive a masterwork from the opera seria repertory of his native city of Naples for the 2009 Salzburg Whitsun Festival season, with additional performances in Paris and Ravenna, offered the opera world the rare opportunity to hear under optimal circumstances a mature work by one of the most acclaimed composers of the mid-eighteenth century, the fourth setting of Pietro Metastasio's Demofoonte composed by Niccolò Jommelli for Naples in 1770.

Audiences hearing Jommelli's music in 2009, probably for the first time, were astonished at its beauty and power. At the same time, some found the neo-classical plot puzzling, if not slightly shocking, and others were confused at having women or men in treble voices singing the heroic roles Jommelli originally composed for the great castrato singers of his day. Fortunately, opera houses and music festivals continue to book operas from this period, for only with frequent exposure can we begin to appreciate the glories of the mid-century classical style, and, regardless of its idiosyncrasies, enjoy it on its own terms rather than as a historic artefact.

In the middle of the eighteenth century the Arcadian reform libretto and the new classical Italian musical style had combined to take Europe by storm. Librettists purged their tragedies of comedy and the supernatural and strove to emulate ancient Greek drama and French classical tragedy. Like his contemporaries, Metastasio focused on heroic figures from ancient history such as Demofoonte. At the same time Italian music had begun to assume periodic aria forms that were clearly classical in process. It avoided polyphony and imitation, concentrating all its attention on a single melody with slowly moving harmonic underpinnings. Despite the seriousness of the text, composers supplied incredibly virtuosic singers with music in a variety of moods ranging from the high style of the rage aria or ‘sea simile’ and the yearning middle style of the unrequited lover's aria d'affetto to the light, charming style of the love song.

Jommelli was particularly admired for his musical eloquence, enhancing the words and the mood with his musical ideas and orchestration. His opera organization in Stuttgart included one of the most famous orchestras in Europe. He pioneered the use of strong dynamic contrasts and developed the crescendo for both structural and dramatic purposes. Jommelli and his close friend the librettist Mattia Verazi strove to make opera more fluid and dramatic by blurring boundaries between recitative and set piece, and breaking up the conventional chain of recitative and exit arias characteristic of the Arcadian reform libretto with orchestrally accompanied recitative, dynamic ensembles, finales, choruses and pantomime.

Many factors have contributed to the tardy revival of opera seria, but now that the opera world is beginning to realize the riches lying in wait, the availability of scores has become a pressing need. Performance-ready conductors' scores with the requisite parts and piano-vocal rehearsal scores are almost non-existent. Scores must be prepared from eighteenth-century manuscripts held mainly in European libraries. Written in archaic clefs, the music must be transcribed into modern clefs and both the parts and the textual underlay correctly aligned. Finally, the fine points of dynamics, articulation and ornamentation must be accurately interpreted from hastily sketched and inconsistent markings in the source, taking care to make clear distinctions in the edition between the original and the editorial notations.

The organizers of the Salzburg Festival in cooperation with the music publishing company Ut Orpheus Edizioni made a significant step towards addressing this problem: they arranged for the publication of a master score of Demofoonte plus a piano-vocal score and collections of arias and ensembles as part of the historic revival and as the first of a series of masterworks from the Neapolitan repertory yet to be selected by Muti. Tarcisio Balbo, who completed a thesis on Jommelli's four settings of Demofoonte for the University of Bologna in 1998 and who has since published several articles on them, was appropriately selected as editor.

Unfortunately, neither an autograph nor a copy by Jommelli's amanuensis Giuseppe Sigismondo survives. From correspondence we know that the director of the Portuguese court theatre, tired of waiting for Jommelli to send a score from Naples, ordered a copy from a Neapolitan copy shop of high repute. Balbo, therefore, elected to base the edition on this copy, which is still held in Lisbon, and to provide a critical report on any deviations from this score that are found in other extant sources, specifically in pitch, rhythmic notation, text and tempo markings. He does not report deviations in articulations and dynamic markings.

Besides the critical notes, the edition includes Balbo's preface in Italian, German and English, a transcription of the libretto and a table of contents providing access to the structure of the opera and the individual numbers. No figures are provided. The score includes pairs of flutes, oboes, trumpets and horns plus first and second violins, viola and bass. All the singers' parts are in the treble clef: five sopranos, one contralto and one tenor. Balbo has produced an excellent, dependable edition. He uses dashed slurs, and brackets for staccatos added editorially to match markings found in the source, but does not bracket dynamic markings he has added. He retains original beaming and flags in the rhythmic notation, and the textual underlay and syllabification are very well done.

If anything I would complain that he did not go far enough in providing editorial guidance regarding articulations. Originally done in a hurry, they are usually marked carelessly in autograph and manuscript copies alike and therefore present a minefield to today's editors and performers. Interpreting the composer's intentions regarding articulation is by far the most difficult challenge facing the editor. Eighteenth-century composers and copyists alike drew slurs above the staff that do not begin or end on specific notes. They were usually sketchily drawn and inconsistent from one bar to the next, or from one part to another in the same bar. They were equally imprecise in indicating to what extent an articulation pattern should be continued and what other parts should also play it – possibly because they knew the musicians would follow the lead of the principal violin, and the maestro di cappella at the harpsichord.

Here a conservative editorial policy has produced an accurate but inconsistent result. Certainly, any musician can see what articulations Jommelli wanted in a passage even though not all are marked, but such imprecision will produce chaos when musicians try to play the parts this score generates. Many of the editorial omissions are hard to fathom, like these examples from the sinfonia: (1) in bars 24 and 28 slurs are not added editorially even when the viola and basses are moving in parallel thirds, placing them in articulative conflict, one legato and the other detached; (2) in bars 24, 26–28, 55 and 57 staccato marks are added in the oboes to match those in the violin, which they are doubling, while the viola and basses are left to plod along without staccato markings; (3) in the beginning of the third movement, where Jommelli introduces a five-bar, four-voice fugato based on a two-bar motive, the editor decided (correctly) to slur only the last two quavers, rather than include the preceding tie, as at least one of the carelessly drawn slurs in the source suggests. Next, all motives lacking slurs in the source needed editorial ones. Why, then, were some marked and not others, and why was there no attempt to reconcile the slurring in the first statement of the fugato with its recapitulation?

In my opinion the editor's role needs to extend beyond simply representing the ‘original’. There is still much work to do before the composer's intentions are fully realized. This is especially true of Jommelli because of the lavish though inconsistent ‘hints’ that are left us regarding his expectations pertaining to articulation and dynamics. If we simply reproduce a given bar in a given part without regard for what is happening motivically in other parts of the orchestra or in the vocal parts (either in that bar or in other repetitions), we leave the musicians at odds when their electronically generated parts do not agree. This leaves the conductor or principal violinist with the real work of making the musical artefact into a work of art. Surely, even if the editor guesses wrong, the dashed slur or bracketed staccato can go a long way towards assisting musical organizations in realizing a new work from an unfamiliar period without great additional toil, while allowing the discerning conductor to fine-tune the realization to his or her satisfaction. In the end, as Jommelli himself advised Bottelho in Portugal, the maestro di cappella will still make the final musical decisions based on what works best in performance (letter from Niccolò Jommelli to Pedro José da Silva Bottelho, 25 September 1770, cited in Marita Petzoldt McClymonds, Niccolò Jommelli: The Last Years, 1769–1774 (Ann Arbor: UMI, 1980), 518).

Despite these issues, which plague every edition of eighteenth-century materials, this new Jommelli edition is a cause for rejoicing. Though it does not answer all of our questions, it offers dependable, long-overdue access to a mid-eighteenth-century operatic masterpiece – one of hundreds yet to be recovered.