The eight chorale preludes presented here for oboe, cor anglais, and two  bassoons, are part of a set of 17 substantial works originally for organ (BWV 651-657) which Johann Sebastian Bach   (1685-1750) put in order towards the end of his life in Leipzig. Although  these revisions took place from about 1744 until 1747, the chorale preludes  themselves actually date from 1708-1717, years when Bach was in the employ of Duke Wilhelm Ernst of Weimar.

1. BWV 651:  Komm, heiliger Geist: Set in ritornello form with a three-voice  imitative ritornello, Bach places the first note of the chorale melody under  the entirety of the initial ritornello. One thinks immediately of Perotin.  After that, Bach proceeds to lay out the chorale in the usual augmented values  (one quarter note to four 16th notes), seemingly separating each phrase of  it with the ritornello. But this is not always the case, because he also uses the chorale melody as the bass harmony of the ritornello blurring the distinction between ritornello and episode.
   
   
2. BWV 655: Herr Jesu Christ, dich uns zu wend: Up to this point, this collection  of chorale preludes has been set in four voices. Now we have before us a work in three voices and in ritornello form, which proceeds without any hint of the chorale melody for the greater part of the movement. To be sure, one is reminded of the 3-voice Inventions. Only at the very end does the bass abandon its supporting role to state the chorale melody.
   
   
3. BWV 656: O Lamm Gottes unschuldig: This item is a set of three variations  upon the famous chorale whose text refers the tripart Agnus Dei of the Mass.  The first two variations concentrate on quadruple subdivision of the beat  in all but the cantus firmus which remains in augmentation. Most of the third  variation is based upon triple subdivision, but the final two phrases of the cantus firmus touch off duple and quadruple subdivision respectively. Throughout the work, Bach interjects short preludes, interludes and postludes, but in no case is ritornello form intended. I have transposed the piece up a half step from A major to the more comfortable double-reed key of Bb major.
   
   
4. BWV 658: Von Gott will ich nicht lassen: Although set in ritornello form,  the ritornello itself is quite motivically-oriented (Affektenlehre); one cannot speak of a ritornello melody as such. The chorale melody glides along in augmentation in the tenor during the episodes, while the other three voices  surround it with the same motive which is central to the ritornello. I have  transposed the piece up a step from F minor to the more comfortable double-reed  key of G minor.
   
   
5. BWV 659: Nun komm der Heiden Heiland:  This is the first of three settings  of this chorale to be found in among the Leipzig Chorales. In this version,  the chorale melody is presented in the highest voice with profuse ornamentation. The three accompanying voices interject interludes between the phrases of  the chorale melody, but this concise work is not to be considered ritornello  form.
   
   
6. BWV 661: Nun komm der Heiden Heiland:  In this exciting final setting, Bach again chooses ritornello form. Here the cantus firmus is placed in the bass in augmented values.
   
   
7. BWV 663: Allein Gott in der Höh’ sei Ehr’: In the second  of this chorale setting the tenor voice carries the ornamented chorale melody. The overall structure is ritornello form driven by two high imitative voices  over the bass. At times, the accompaniment of these three voices is sparse causing the overall texture to boarder on recitative secco.
   
   
8. BWV 664: Allein Gott in der Höh’ sei Ehr’: In the third  and final setting of this chorale, Bach reduces the texture from four to three voices and proceeds to compose the second movement of a trio sonata in ritornello form. At the very end, he introduces the first two lines of the chorale melody in the bass. I have transposed the piece up a half step from A major to the more comfortable double-reed key of Bb major.