Summary of Bach Chorale Harmonisation Method Step 1: Keys and Cadences 1a - Keys Work out the home key and the five closely related keys. Explanation and Example 1b - Cadences For each pause, work out the most likely key and cadence. Explanation and Example Check 1 Now play through the melody twice, once on its own and then with the final two notes of each phrase harmonised with the bass notes (and if possible the chords) from your chosen cadences. If a cadence does not sound right, try alternative harmonisations Step 2: Simple harmonisation 2a - Modulations Now you know what keys the cadences are in, you need to plan where and how you are going to modulate. Explanation and Example 2b - Primary chord harmonisation Complete the rest of the chorale using primary chords only (I, IV and V) in root position. There is no need to worry about voice-leading or writing a good bass line at this stage. Explanation and Example Step 3: Refining the bass line 3a - Fingerprints Check whether you can fit in cadence patterns that are characteristic fingerprints of Bach's chorale style Explanation and Example 3b - Rewriting bass line Re-write your bass line for the rest of each phrase to improve the voice-leading, including eliminating parallels. Explanation and Example Check 2 Now play through the bass line and soprano on the keyboard, checking in particular for parallels from the Double SLAP Step 4: Adding inner parts 4 - inner parts Complete the inner parts, being particularly careful with Spacing rules Explanation and Example Check 3 Now check obsessively for all of the possible problems outlined in the Double SLAP. If possible play all four parts but you should at least play each part individually, preferably with the bass. Explanation and Example