Johann Sebastian Bach (1685-1750) and the organ
Although Bach was not occupied exclusively as an organist, his name and his works are clearly associated with the organ. He was acquainted with the instrument from his earliest years. At around ten years of age (following the death of his parents), he was taken in by his elder brother, Johann Christoph, the organist of Ohrdruf, and his family, and from 1700-2 he was a pupil at the Michaelis School in Lüneburg, where he probably came into contact with Georg Böhm (organist of St Johannis) and with the organ-builder Johann Balthasar Held (a pupil of the famous Arp Schnitger). From Lüneburg he journied to Hamburg where he heard Johann Adam Reincken (organist of St Catherinen) play; he later met Reincken (in 1720) when he applied for the organist’s position at St Jacobi, Hamburg. At the end of 1705 Bach travelled on foot to Lübeck to hear Dietrich Buxtehude, the renowned organist, play; he remained there for three months! Bach received his first appointment in 1703 at St Bonifacius in Arnstadt, and his nomination to the organistship (which included duties as a church musician) of St Blasius, Mühlhausen followed in 1707. From 1708 to 1717 Bach was employed as the court organist at Weimar, where he wrote the majority of his works for organ. Subsequently he served as Kapellmeister to the court at Cöthen (1717-23). In his capacity as Kapellmeister he was expected to write church cantatas for specific occasions. Although it is uncertain whether Bach had to fulfil duties as an organist, various organ works date from this period. His last appointment was as Kantor at St Thomas’s Church, Leipzig (1723-50). There he was responsible for the church’s music (both as composer and director), but, as at Cöthen, there was no specific task for him as an organist; this seemed to be no obstacle to his composing numerous works for the instrument. In earlier centuries it was the norm for composers to write functional music. Bach was no exception to this. Not only the chorale-based works, clearly written for specific times in the Church Year, but also most of the ‘free’ organ works can be accorded a place in the liturgy. Research on this point must undoubtedly be considered both speculative and challenging; through such inquiry, however, unexpected perspectives can be gained.

The ‘Bach organ’
Many authors have considered questions about the type of organ that is most ideal for the interpretation of Bach’s organ works. The notion of a ‘Bach Organ’ quickly established itself. All things considered, the conclusion can only be that the ‘Bach Organ’ is an unattainable and utopian ideal. Bach had extensive knowledge of organ-building and came into contact with builders from differing German organbuilding traditions. His own sphere was Thuringia and Saxony, a region where a multitude of influences from other areas can be observed, and which possessed its own indigenous types of organ. Bach became acquainted with, and played on, instruments of all traditions, and undoubtedly thought about these types of instrument in course of writing down his compositions. The eclectic nature of Bach’s works for organ equates, as it were, with the diversity of the organ timbres he encountered. The versatility of his organ compositions, with their immense stylistic palette, makes for performance on organs of different traditions not only possible but even desirable. Registrations In choosing registrations for his Bach recordings, Jacques van Oortmerssen is following exactly Bach’s (infrequent) indications for the use of one or more manual(s) and forte/piano dynamics. Moreover, he is basing his interpretations on that which is known about registrational practices in Bach’s time and region; in this respect the surviving prescriptions of Georg Friedrich Kauffmann (1733-6) and Jacob Adlung (1758) are particularly useful. For the plena of the large ‘free’ works, he is following conventions that are rooted in older traditions. Trio textures are registered with timbres that correspond to instruments commonly used in trio compositions. A colourful spectrum is thus brought to life, and the player is therefore able to illustrate the diverse Affekten of Bach’s music more effectively.

The Doctrines of Affections (Affektenlehre) and Musical Figures (Figurenlehre)
Music can evoke different states of mind, or, as the German Baroque commentator would have rendered it, different Affekten. According to contemporaneous thinking, the composer had to concern himself with inducing a specific state of mind in the listener through his music. One can distinguish different Affekten. Simply, they can be separated into two main categories: joy and sadness. Affekten can also be intense or less intense, positive or negative. A composer relied on a variety of means to evoke Affekten: different keys, a specific tempo and rhythm, harsh or less harshly dissonant intervals, etc. The rules of Classical rhetoric formed, for the Baroque composer, a departure point for the design of a piece. With the help of comprehensive Figurenlehre (musical figurations and formulae) he could subsequently fill in the details.

The Preludes and Fugues
For nearly forty years Bach was occupied with the writing (or revision) of ‘free’ works under the titles of ‘Prelude’, ‘Prelude et/ con Fuga’, ‘Fuga’, ‘Toccata’, ‘Toccata con Fuga’, ‘Fantasia’ and ‘Fantasia con Fuga’. When one summarises these categories under the name ‘Preludes and Fugues’, and compares them with similar compositions from the time before Bach, it must be acknowledged that Bach brought this form to a synthesis from northern and southern German preludial and fugal idioms. In North Germany preludes and fugues were multisectional pieces, in which ‘free’ sections alternated with fugal sections, and in South Germany preludes and fugues were separate, individual movements (or works). With his synthesis Bach is recognised as having brought this compositional form to a (new) culmination; since Bach’s death these works have enjoyed an almost unbroken popularity. Over the long period in which the works in this form were written, an exciting development can be traced. We can distinguish six different types, from a continuous form in the early works to a convincing concerto-like form in the later compositions. In the early works we find successive influences from South Germany, France, and North Germany, and in the later works, the application of Italianate influences (including many string-playing styles) resulted in forms imitating concertos (in which the tutti and soli sections converse with one another), or the use of ritornelli (refrain-like sections).

The Concertos
Various arrangements by Bach are known as ‘concerti’. They are works that other composers wrote for orchestra: six for organ (BWV 592-596) and 16 for a keyboard instrument without pedal (BWV 972-987). (In addition to BWV 592, there also exists a version without pedal, BWV 592a.) Among the composers of the original works for orchestra are Vivaldi, Telemann, Marcello, and Prince Johann-Ernst of Sachsen-Weimar. Interestingly, the motive for writing such arrangements - probably at the behest of Prince Johann Ernst - is to be found in a Dutch practice. The Prince (1696-1715) studied, from 1711 to 1713, at Utrecht University. During his residence in The Netherlands he travelled to (amongst other places) Amsterdam; it is most probable that whilst there he heard the blind organist of the Nieuwe Kerk, Jan Jacob de Graaf (c. 1672-1738), play. De Graaf played Italian concertos and sonatas on the organ, so it is therefore plausible that, on his return to Weimar, the Prince commissioned Bach (and also his own composition teacher, Johann Gottfried Walther) to make similar arrangements for organ and for keyboard instrument without pedal. The dating of these works (from the years 1713-4) is quite certain.

The Chorale Settings
Bach’s chorale settings for organ have survived mainly in collections: the ’Neumeister-Sammlung’ - discovered in 1985 - containing BWV 714, 719, 742, 957, 1090- 1120; the ’Orgel-Büchlein’ (BWV 599-644); the ’Schübler-Choräle’ (BWV 645-650); and the ’Leipziger-Choräle’ (BWV 651-668). The third part of the ’Clavier-Übung’ (a self-contained work) comprises 21 chorale settings. Finally, there are more than 40 settings which may be divided into two groups: BWV 690-713 (from the ’Kirnberger Collection’) and BWV 714-764 (works surviving separately in a number of diverse manuscripts). In these last two groups are works which in the past have been either wrongly attributed to Bach or are of doubtful authorship. Together there are nearly 170 chorale settings, not counting 20 or so variants. Every conceivable way of treating a chorale melody for organ is employed by Bach, and the early settings show the way in which he experimented with forms, models, and ornamentation. His chorale settings offer a true sample of his works, from short, simple settings to long, freely worked trios; an output which knew no limits!

Prelude and Fugue in C major BWV 531
This Prelude and Fugue can be considered as an early work (dating from the period 1700-1703) and it shows many similarities with the Prelude and Fugue in C major by Georg Böhm (1661-1733), with whom he was probably in contact at that time. Influences from other North German composers are also discernable. The Prelude, which begins with a long solo for the pedal (a head motif, many broken chords, and passagework), effervesces with youthful impetuosity. Even the last few bars of the Prelude – a chain of chords to prepare the ending – are worked out virtuosically with interlocking chords and passagework. It is a beautiful example of the stylus phantasticus. The agile fugue theme with both its octave leaps – providing a repeated note with a very individual effect – continues the momentum of the Prelude most effectively. A long coda, ending with an organ point in the pedal, brings the Fugue to a resolution; as with the Prelude’s conclusion, rapid passagework drives the movement towards its end.

Trio in G major BWV 1027a
Bach wrote much chamber music as Kapellmeister to the court at Cöthen (1717- 1723). Among other works, three Sonatas for Harpsichord and Viola da Gamba (BWV 1027-1029) belong to this period. A version of the first Sonata in G major exists for transverse flute and continuo (BWV 1039) but with other tempo/character indications. The suspicion is that this last version is the original composition which Bach later reworked for harpsichord and gamba. The fourth movement of the Sonata, which survives in the so-called ‘Mempell-Preller Collection’ in Leipzig, is also arranged for organ (BWV 1027a). The author of the transcription is unknown, but it is doubtful that it was Bach himself. The source for this version is faulty so Jacques van Oortmerssen has ‘restored’ the arrangement for this recording.

Fantasia super ‘Christ lag in Todesbanden’ BWV 695
The melody of the Easter chorale ‘Christ lag in Todesbanden’ is to be found in this short fantasia in the alto voice. The work comes from the ‘Kirnberger Collection’ and dates from Bach’s years in Weimar (1708-1717). In a certain sense it is a twopart composition with an added chorale melody, from which the composer has fashioned two melodic fragments into a refrain: the first he uses at the beginning (and exclusively at the end) and the second after the repeat of the first melody line.

Allabreve in D major BWV 589
‘Allabreve’ is the indication for a stipulated time signature in which the beat falls on the ‘brevis’ (in our notation the minim or halfnote). The term was also used as a name for a piece of music which was written in such a time signature, constructed contrapuntally, and whose character was fundamentally serious. In the Kirchenstyl one used this time signature to write pieces with a gravitätisch character. Two of the three sources in which this piece survive, mention the title ‘Allabreve con Pedal con Organo Pleno’. A dating is difficult because the work is not preserved in Bach’s hand, and the oldest known source to date is, at the earliest, from 1740-50. There are even musicologists who dispute Bach’s authorship. Italianate in style, thematic concordances with the third part of Corelli’s Concerto Grosso op.6, no.1 (1712) can be seen.

‘Herzlich tut mich verlangen’ BWV 727 & ‘Erbarm’ dich mein, O Herre Gott’ BWV 721
These two chorale settings, also dating from the Weimar period, are to be found in a manuscript preserved in Berlin (Mus. ms. Bach P802) and in which the hands, among others, of Johann Gottfried Walther and Johann Tobias Krebs can be recognised. Another copy of ‘Herzlich tut mich’ exists (a J.G. Walther manuscript in the library of the Gemeentemuseum, The Hague), but ‘Erbarm’ dich’ is known from one source only. ‘Herzlich tut mich verlangen’ (à 2 Clav. e ped.) corresponds to the style found in the ‘Orgel-Büchlein’ settings. The economically ornamented melody lies in the soprano and must be played with a distinctive stop. The simplicity of the composition’s construction illustrates beautifully the directness of the chorale text, which expresses the longing for death. ‘Erbarm’ dich mein, O Herre Gott’ can be considered unique in Bach’s oeuvre, Earlier researchers discounted this as one of his works. The similarity with a movement from a similarly titled cantata by Ludwig Busbetzky, a pupil of Dietrich Buxtehude, is striking. The accompaniment consists of just three or four part chords against the melody moving in long note values in the soprano line. With the help of some writhing dissonances, this setting illustrates the text perfectly.

Concerto in d minor BWV 974
The Oboe Concerto by Alessandro Marcello (1684 – 1750) is the basis for this keyboard (without pedal) transcription by Bach. The first movement of this wellknown and popular work has the character indication Andante e spicato in the 1716 Amsterdam edition; there is no indication for this movement in Bach’s arrangement. The second and third movements, however, indicate Adagio and Presto respectively. The difference between the writing in the first and third movements is striking; in the first movement the orchestral portions in a number of passages are ‘translated’ more closely than in the third movement. In the middle movement Bach limits himself to a melody and a two or three part accompaniment; only the closing orchestral bars show fuller writing.

Prelude in a minor BWV 569
One four note motif forms the foundation of this composition and dominates the score practically from the beginning. After a short three bar introduction, it appears in miscellaneous rhythmical and melodic forms in all voices, and in ingenious ‘variations’. Bach pushes to the limit the use of a sequence (the literal reputation of a fragment at another pitch) – again an example of Bach’s urge to experiment. The title page carries the heading ‘Praeludium pro Organo pleno con Pedal’ in one of the important sources (not Bach’s handwriting but preserved in several pupils’ copies) for this Prelude. Opinion is divided over Bach’s authorship as well as the composition date of this work.The sources seem to confirm the authorship and the period of its composition can be set from 1703 to 1717.

Canzona in d minor BWV 588
The instrumental canzona, originally an arrangement of the French vocal ‘chanson’, was first encountered in Italy. The keyboard canzona developed into a separate genre; from arrangement in the beginning to an independent composi - tion with an obstinate and consistently recognisable thematic structure. Bach’s Canzona for organ (his only composition in the genre) is an early work and can be dated around 1715. It comprises two sections: the first in a duple, the second (with a derived theme) with a triple time signature. Striking thematic similarities can be seen with two Italian works: a canzona by Girolamo Frescobaldi from ‘Fiori musicali’ (of which Bach obtained a copy around 1714), and also with a canzona by Domenico Zipoli.

Fugue in G major BWV 576
Although there are reasons to doubt Bach’s authorship of this Fugue, there are certainly ingenious passages that make an attribution to Bach’s youthful hand attractive. The light theme, as well as the progress of the harmonic scheme, could pass perfectly for an Italian sonata or an Italian concerto grosso. Of particular interest are the last two bars which use the opening of the theme twice to bring the fugue to a firm conclusion.

‘Herr Jesu Christ, dich zu uns wend’ BWV 709
Like BWV 695, this chorale prelude à 2 claviers et pédale originates from the ‘Kirnberger Collection’ and dates from Bach’s Weimar years. The richly ornamented chorale melody appears in the soprano, each new chorale line starting with a trilled long note. One could consider the ornamentation techniques used here to be based on a combination of French and Italian principles. A pair of characteristic motifs, which are not borrowed from the melody, supply the building blocks for the accompanying voices.

Toccata and Fugue in d minor BWV 538
The Toccata and Fugue in d minor has become known as ‘the Dorian’, a name (pointing to the use of the Dorian mode) which it carries unjustly. The work can be dated with certainty from the period 1712-1717. The Toccata is a beautiful example of the concertato style in which tutti and soli alternate in a splendid dialogue. One could title the Toccata as the first movement of an original ‘concerto grosso’ for organ. The lively movement in semiquavers or sixteenth notes, from which the theme is crafted, is sustained throughout the work. The developing propulsion becomes infectious for the listener. The ‘rigour’ of the Fugue contrasts with the vivacity’ of the Toccata; both balance one another in the totality of the composition. The Fugue’s complex construction points to Bach’s craftmanship in this genre. Its theme spans and fills in a whole octave with both ascending and descending lines. Despite the complicated structure and architecture, the Fugue avoids artifice through Bach’s ability to imbue such a theme and its working out with lyricism. There are no connections apparent between Toccata and Fugue but closer consideration of the Fugue’s theme reveals that the first half of the theme is to be found in the first three bars of the alto voice in the Toccata. This serious Fugue employs syncopations, dissonances and an alla breve time signature.