The appearance of the landmark collection L'Estro armonico (Amsterdam: Estienne Roger, 1711) – his Op. 3 – catapulted Vivaldi into international fame as a leading composer of instrumental concertos and helped initiate a transalpine craze for North Italian-influenced solo concertos. Anticipating demand for a follow-up collection, Vivaldi included a letter in Op. 3 in which he promised another collection to follow shortly. The varied disposition of the works in Op. 3 required a minimum of eight partbooks, so Vivaldi promised the next collection would have fewer parts and thus be more affordable for those who found the required materials to be an expensive proposition. Several years elapsed before Op. 4 appeared, even though evidence suggests the concertos found in Op. 4 were submitted to the publisher around the time Op. 3 was published. During this intervening period, Vivaldi began to establish himself as a prominent composer and impresario for Venetian operatic theatres and became increasingly involved in compositional duties at the Pio Ospedale della Pietà.

Eager to ensure that this second collection of concertos live up to the excitement generated by Op. 3, Vivaldi focused on building even more invention, drama and surprises into his harmonic, rhythmic and textural vocabulary. He gave the set the title La stravaganza (‘Extravagance’), and several aspects of his experimentation throughout the set are among the boldest ideas to be found in his published works. While not quite reaching the same level of acclaim as his Op. 3, La stravaganza was very well received. The concertos were reprinted and reissued several times – as a whole and as part of small sets of ‘favourite’ concertos.

The present edition by Bettina Schwemer partially draws upon work begun by the late Christopher Hogwood in preparation for his own edition, which was left uncompleted at the time of his death. The twelve concertos of Op. 4 are published in score alongside several alternative versions and related works (rv291 – added to Walsh and Hare's 1728 edition of Op. 4 – along with rv383 and the first movement of rv381, the latter two related to Concerto 1 of the set). A violin-piano reduction and performance parts (the latter not reviewed here) are also available. The concertos of Op. 4 were previously edited and published as individual scores within the series Le opere di Antonio Vivaldi (ed. G. F. Malipiero and others (Milan: Ricordi, 1947–1972)), which also included editions of rv291, 381 and 383 but omitted the manuscript variants of Concertos 2, 3, 6, 10, 11 and 12. The Roger edition (in parts) has been offered in facsimile on at least two occasions, and individual concertos have appeared in numerous other editions (generally intended for performance use) since the 1940s.

One advantage to this new edition is that it combines all of the concertos in only two volumes and, unlike the earlier Ricordi edition, provides a discussion of the sources and a critical report (repeated in both volumes and retained in the piano reduction). The Bärenreiter edition of the score also provides a much more useful layout: the full-size format and the absence of the continuo realizations and editorially created contrabasso parts of the Ricordi edition allow for three systems to appear on each page and up to ten bars per system, eliminating the need for page turns every six or eight bars in fast movements. For the most part, the notation has been silently modernized, but discrepancies between text and source are noted in the Critical Report. The sparse editorial additions are clearly indicated.

We do not have autograph manuscripts for the concertos of Op. 4, and most of the surviving manuscript scores and parts contain significantly different versions of the material, for which Vivaldi's authorship is not entirely secure. Schwemer has opted to provide full texts for several – but not all – of the significant manuscript variants, many of which have not previously been edited for commercial publication. The Preface describes the sources for each concerto and in ‘Notes on the Edition’ Schwemer gives the justification for deciding which works to include in full. In general, variant texts are provided if there is a possibility that Vivaldi was at least partially responsible for the divergences from the Op. 4 versions, even if it is also suspected that another person (especially for manuscripts associated with J. G. Pisendel) introduced further divergences. In the case of two works – Concertos 6 and 11 – a common assertion is that the manuscript versions (which lack viola parts and contain other substantial variants that tend to simplify the material) may represent early, pre-Op. 4 versions. However, Schwemer is wise to remain noncommittal, since the evidence is hardly conclusive; several factors suggest local circumstances might account for some or all of the divergences.

One area where Schwemer is less consistent is in the inclusion of concertos that share individual movements with the works of Op. 4. Perhaps owing to their delayed publication and Vivaldi's willingness (in keeping with common practice of the time) to reuse and recombine material in response to specific individuals and occasions, variants of entire movements from three concertos (Nos 1, 6 and 9) are found in no fewer than five additional concertos, and the main themes of the slow movement of Concerto 12 and the finale of Concerto 7 also appear in other works. Oddly, Schwemer includes rv383 (which pairs a new first movement with alternative versions of the second and third movements of Concerto 1), but provides only the first movement of rv381 (which combines a variant of the first movement of Concerto 1 with new second and third movements); both concertos are equally ‘related’ to Concerto 1. The edition does not contain a reference to or score for the concerto rv285, which joins a variant of the first movement of Concerto 9 to a different second and third movement. As all such reuses of movements are mentioned in the literature cited in the general bibliography, it is unfortunate that the edition does not mention that Concertos 7, 9 and 12 share material with several other Vivaldi works.

In general, the notes are informative, although they contain a few errors and unsubstantiated claims. For instance, the source information for Concertos 5 and 6 was accidentally conflated so that a source for Concerto 5 (D-DS MS 4446 – now lost) is incorrectly described as containing a variant (rv316) of Concerto 6, and the actual source of that variant (D-DS MS 4443 – also now lost) is left out entirely. In discussing arrangements and transcriptions made by Vivaldi's contemporaries, Schwemer acknowledges the keyboard arrangements by J. S. Bach and those found in Anne Dawson's keyboard manuscript, but neglects to mention that the opening movements of Concertos 1 and 5 are also preserved in anonymous keyboard transcriptions in a manuscript held in the Fitzwilliam Museum (GB-Cfm, 52-C-11), that thematic material from Concertos 6 and 7 was used in Nicholas Chédeville's pastiche Il pastor fido (Paris: Boivin, 1737) or that a portion of the opening of Concerto 1 was published in The Musical Pocket Book (London: J. Simpson, c1750). She also reiterates, without supporting evidence, the often-repeated claim that the use of the viola was optional. Considering that the part was not sold under the rubric ‘ad libitum’ and frequently plays melodic and bassetto roles in these works (not to mention making significant harmonic, rhythmic and textural contributions), such a broadly applied statement mischaracterizes the music.

The reduction for violin and piano has a very clean appearance and is for the most part easy to use. The violin part is designed with a few fold-out pages to avoid page-turns in the middle of a movement, although this device was not used in either version of Concertos 2 and 12, which require impossibly fast page turns in their finales. Schwemer's decision to retain the original shorthand notation (as sustained chords) for extended arpeggio patterns leaves the performer to guess at how exactly to realize these passages (deciding, for instance, whether lower neighbours should be played as tones or semitones across changing harmonic contexts). Accompanists may also find the piano reduction a bit difficult to use as it stands. In odd contrast to the very sparing and primarily chordal realizations of the passages accompanied only by basso continuo, the remainder of the reduction is very dense, trying as it does to accommodate all of the original lines of the texture regardless of how well the result fits under the fingers; there are stretches as wide as a tenth, rapid scales in parallel thirds and repeated notes for one or two fingers while the rest of the same hand plays other busy gestures.

While it has a few shortcomings that are particularly unfortunate given the price and prestige of the edition, this is the best critical edition currently available for these works. The fact that several variant versions are printed in full is particularly welcome. Regardless of the extent to which they were or were not produced with Vivaldi's knowledge, these variants speak to the popularity of his works and bring modern performers into contact with eighteenth-century ideas about adapting and revising pieces to suit the occasion – with all of the potential limitations and rewards that are involved.