Here is a further volume of the ongoing C. P. E. Bach Complete Edition; it presents three keyboard concertos, one of them in two distinct versions. As we have come to expect of this enterprise, the scholarship is of the highest order, and the volume is handsomely, indeed sumptuously, produced. Its modest price – a mere $25 according to the edition's website – is therefore a welcome surprise. The general introductory material describes the editorial processes that have been followed, discusses the three relevant concertos in some detail, briefly considers a few issues of performance practice and lists keyboard concertos once attributed to C. P. E. Bach but which are now considered doubtful or spurious. (I was amused to read that a Concerto in D major listed in some of the literature is actually a forgery by Henri Casadesus.)

We perhaps forget that Emanuel Bach left as many as fifty-two keyboard concertos, as listed in the ‘Nachlaß-Verzeichnis’ which was published in Hamburg in 1790. This comprehensive and significant index of Bach's oeuvre is based on the composer's own catalogue, which he had been compiling methodically for some years. Like his father, Emanuel constantly revised his compositions, and this is the case with all three works in this new edition. They are the Concerto in A minor Wq1, given in two versions; the Concerto in E flat major Wq2; and that in G major Wq3. All have come down to us in manuscript sources only, which are fully described in the edition. (Also included are details for each concerto of manuscript sources which have been consulted but not used.)

The ‘early’ version of Wq1 was written in Leipzig in 1733, and subsequently revised in 1744, by which time the composer was in Berlin as a chamber musician at the Prussian court. It was probably also performed in Emanuel's concert series in Frankfurt an der Oder, where he was based from September 1734. This was the ‘Musikalische Akademie’ he mentions in his autobiography – a student body which he directed. Almost all of Emanuel's pre-Berlin works have been lost, or conceivably were destroyed by him when he made revisions. However, it seems that Wq1 was a favourite concerto which enjoyed considerable popularity and which he allowed to circulate, unlike other works that he withheld (perhaps to retain them for his own exclusive use). This new edition provides the opportunity for close comparison of the two versions, allowing us to examine the revisions carefully. Wollny clearly outlines the essentials of these revisions in the Introduction, and informative details of all the various sources are included in the Critical Commentary. This has involved considerable editorial labour, not least because there are variant readings even within the sources of the early version.

In the 1730s Sebastian Bach's Leipzig Collegium Musicum concerts were flourishing, with twice-weekly meetings, and we know that his own keyboard concertos, both solo and multiple, were intended for performance there. The Bach sons were of course heavily involved, and Emanuel was active both as performer and as copyist; his Concerto in A minor Wq1 was probably first heard at one of those concerts. The earliest source is in the hand of Sebastian's pupil Johann Friedrich Agricola; it therefore dates from the same period as his father's keyboard concertos (most of which are of course arrangements). The work gives plenty of scope for keyboard virtuosity, and already exhibits many of Emanuel's characteristic traits: not least in its clean, sometimes sparse writing, harmonic surprises, repeated-quaver bass lines and unison string textures. By the time of the 1744 revision, Emanuel's compositional skills had grown, and we find him (as Wollny states in the Introduction) ‘attempt[ing] to work out the basic musical idea underlying each movement in a more effective way’ (xiii). Also notable is the fact that, in the slow movement, ‘the relationship between the solo instrument and the string ensemble is completely redefined’ (xiii). This is not the place to outline all the changes Bach made in this piece; suffice it to say that the revisions were comprehensive. Even after 1744, according to Wollny, Bach continued to clarify details of the piece (xiii). It is fascinating to learn that some of the source material for the later version is in J. S. Bach's hand (xx); he copied the keyboard part, the two violin parts and one page of the viola part, but stopped at that point for unknown reasons. Much later, probably in the 1760s, Emanuel completed the set, and made yet more revisions. (Among the facsimile pages included in the edition is the first page of Sebastian's keyboard part, with some additions in Emanuel's hand.)

The other two concertos in the edition also date from the Leipzig years – 1734 and 1737 respectively – but are extant only in Berlin revisions made in 1743 and 1745. Again, a number of sources exist but all date from no earlier than the mid-1740s. Wollny is convinced that these two works underwent the same kinds of revisions as did Wq1, justifying his opinion in the Introduction with detailed comment. He feels that they ‘appear to have been thoroughly adapted to the style of the Berlin works from the mid-1740s’ (xiv). Both are extensive pieces, with lengthy and elaborate ritornellos that set forth the musical material to be explored and developed; as with the revision of Wq1, the writing for soloist and orchestra is skilfully and effectively integrated.

In addition to the critical apparatus at the end of the volume, an Appendix contains ‘Alternate Solo Keyboard Parts’ for the slow movement of Wq1 (early version) and for the whole of Wq2. Wollny feels that these sources are sufficiently different from the principal readings to justify inclusion, and so again informative comparisons can be made. Completing this Appendix are three contemporary cadenzas, one for each movement of Wq2, which are found in a set of parts in the hand of Johann Heinrich Grave.

The edition seems extremely accurate and free of misprints or other infelicities. All I have noticed is a probable missing G♮ in bar 40 of Wq1 (early version), in the bass line of the keyboard part. The edition's website invites users to communicate any corrigenda or addenda which they feel may be necessary, and carries a list of these for each volume already published. (They are few in number.) At all events, these are fine concertos which deserve to be more frequently performed. This splendid new edition, clearly laid out and beautifully produced, should encourage musicians to do just that.