So today I thought I'll give you a quick overview of the steps necessary to improvise such piece. I'll take a model from an actual composition - BWV 556 because it's a concise, simple, easy, and extremely listener-friendly piece.
So here are the steps for improvising the prelude:
1. Choose a key (major or minor), meter, and a figure (rhythmical and/or melodic). Hint: it could be a triplet figure from BWV 556 or from any other Baroque piece that you love. To make it simple, we will use one figure exclusively throughout the prelude.
2. Play a 4 measure introduction which establishes the home key and finish with the half cadence (end on the Dominant). No pedals.
3. Play a sequence going through closely related keys up or down and finish in the home key with a perfect cadence (about 10 measures). With pedals.
4. Play 3 phrases. Phrase 1: start in the tonic key and end on the Dominant (4 measures). Phrase 2: repeat the same phrase a step higher or lower (if a home key is minor - 4 measures). Phrase 3: start on where you ended Phrase 2 and finish on the relative key (6 measures). No pedals.
5. Start in the tonic key and end on the dominant (6 measures). No pedals.
6. Repeat Step 3 starting on the dominant but end on the relative of the dominant (about 10 measures). With pedals.
7. Repeat the Steps 2 and 3 exactly. This ends the prelude. To connect Step 6 with 7, you can include a short modulation going from the relative of the dominant to the tonic key.
The steps for improvising the fugue:
1. Choose a meter and a theme (subject) of 2-3 measures long.
2. Exposition: play the subject in tenor (tonic key) with the left hand. Other voices are silent.
3. Play the answer in alto (dominant key) with the right hand. Tenor plays counter-subject at that time which contrasts with the subject rhythmically and melodically. Tip: do not mix duplets and triplets together into one subject or counter-subject. End in the tonic.
4. Play the subject in the soprano with the right hand (tonic key). Alto and tenor (the left hand) move as little as possible.
5. Play the answer in the bass with pedals (dominant key). One of the three upper voices play in paralel thirds or sixths with the bass. This concludes the exposition (end in the dominant).
6. With soprano silent, play a 2 measure sequence with the material taken from the subject.
7. Counter-exposition: play the answer in the soprano in the dominant key (4 voice texture with pedals).
8. With the pedals silent, play a 2 measure sequence leading to the tonic key.
9. Play the theme in the pedals in the tonic key (4 voice texture).
10. Play 2 measure interlude with the material from the subject in the soprano (4 voices with pedals).
11. Play the answer in the pedals in the dominant key (4 voice texture).
12. Play the answer in the soprano in the dominant key (4 voices with pedals). At the end make a modulation to the tonic and conlude wih a perfect cadence in the home key.
1. Print out these steps and write your pieces on the paper first.
2. Play them on the organ from the notes.
3. Put this verbal outline on the music rack and play from it.
4. Remove the outline and improvise without any help of the paper.
To your success in improvisation,
P.S. By the way, in less than 9 hours I'm closing the registration for the free video mini course in mastering BWV 556 in 7 days. If you haven't done so, go here and sign up for free (131 people are already in):