Harmonizing a Bach Chorale

[abacaba]

When I am working on harmonizing Bach Chorales, this pattern of ascending bass with sharps (see attached: C# - D#) comes up in many cases. What is the standard way of harmonizing it?
1. Treat it as an ascending melodic minor fragment of 6th and 7th leading to the tonic?
2. Assign a chord to each one of them?
3. Assign one as a chromatic passing note?
Thanks for shedding light on this.

[sammy248]

Definitely sounds like melodic minor going to the E relative minor tonic.  The implied chord, to me, is a V in E minor (or a vii diminished).

Also, check your chord on the next two bass notes, E and F# -- Right now it's labelled as IV6.  I think it should be an Emin chord on the E bass.  C#-D#-E  implies V going to i (or vii dim to i) in the relative minor, so it sounds better to let it go where it wants, i.e. to the E minor tonic chord.

The following F# could either be a passing note over the E min chord, or it could be D/F# (in Roman numerals, V6 in the key of G).

That's what I'm thinking, anyway : ). Let me know your thoughts.

[yale_music]

Good question, abacaba. This is an interesting case, which you find a fair bit in Bach's chorales. Sammy is on the right track: you're dealing with applied chords here. Your IV6 chord should be a VI chord (E minor), and the C# and D# support applied chord to E minor. In other words, your progression (from the start of the example) should be as follows:

V6/5 - I - [IV6/5 i V6/5] of VI - VI - dominant of some kind - I - V7 - I

Over the bass C# you need A (given) E and G, and over the bass D# you need B F# and A (given).

I hope this helps.

[falala]

Yale has nailed it, except that I wouldn't say you definitely need a 7th (G) in the chord over the C#. It could just be a plain A triad - IV of E minor.