North German chorale fantasia

A large-scale organ work based on a Lutheran chorale melody, in which successive lines of the hymn are elaborated in contrasting styles — cantus firmus in the pedal, ornate melodic variation, imitative entries, echo effects. Buxtehude's chorale fantasias are the most ambitious examples of the form.

In a chorale fantasia each section should feel like a fresh discovery of the same melody. Registration changes between sections are idiomatic and expected. Keep the cantus firmus clear and slightly prominent; the surrounding counterpoint is commentary, not competition. Long pedal notes need a strong toe technique and a sense of harmonic arrival.