# How to part write I6 to IV with parallel 10ths in the outer voices

In this first phrase of a part writing exercise I have been given ( "Harmony and Voice leading 5th edition") a figured Bass and the few soprano tones marked with red dots. I am stuck right at the end where there is an ascending soprano moving in parallel tenths with the Baseline. The very last beat is tricky because if I double the bass and tenor Bb I will not be able to move to the C at the semicadence without a parallel unison or overlaps. If I double the 3rd of the Bbm chord I will have parallel octaves with soprano. Have I made an error in the previous harmonizations to not be able to get past to the cadence? Can anyone give me some alternatives solutions please?

• Please indicate the source of the exercise material. Commented Apr 26, 2022 at 13:37

The outer voice move by tenths then contrary motion to an octave on the dominant.

First complete the triadic harmony with `F` for root and fifth of chords and `E` natural for the third of the `V` (which is still incomplete, but that's OK.)

The rest is about what to double and how to avoid forbidden motions. The outer voices and first inner voice are all OK, so we really only need worry about parallel fifths and octaves rather than direct fifths and octaves.

Going by the rule of thumb to double tonal degrees we can try doubling the tonic `F` or the dominant `C`.

It seems to me the question isn't how to get from `i6` to `iv`, but how to get from `iv` to `V`. With root progression by step you want to move all the upper voice contrary to the bass. When you do that with `IV` to `V` the scale degree `^4` subdominant will go down to the `^2` supertonic (`^1` goes to `^7` and `^6` goes to `^5`.) So, whether the doubled tone is `F` or `C`, move it to the subdominant then to the supertonic.

• Thank you, the 3rd option has 2 leaps of a 4th in the inner voices... not really great, the others seem smoother but you didnt show the previous voice leading. That would have leaps coming from the 43 chord... so it just seems that one way or another this progression is going to have big leaps. I was worried something I did before might have given me a smoother progression... not gonna happen
– user35708
Commented Apr 27, 2022 at 20:15
• What is the problem with leaps, especially when just arpeggiating the chord? If the goal is to have all voices moving only by step, the results will be dull. Your actual situation is complete except for one note each for alto and tenor, you're left with few options. Commented Apr 28, 2022 at 16:16
• I think there could be more to say if you provided the complete, original exercise along with what you wrote. Sometimes writing the cadences first, then the opening, then the interior of phrases, sort of working backward rather that straight start to finish, makes it easier to get a satisfying result and minimize the compromises to only insignificant moments. Commented Apr 28, 2022 at 16:16
• Thanks Michael. The bar in question is not arpeggiating one chord. According to several of my textbooks , leaps are best left for the soprano and bass.. the middle voices should be static and just kind of support the outer voices...
– user35708
Commented Apr 28, 2022 at 17:50
• My mistake! But, this it's OK to make a leap like that. Commented Apr 28, 2022 at 18:11

How about something along the lines of the following? (The third possibility doesn't completely reflect the figures I admit...) None of them is particularly elegant - I agree it's a slightly awkward passage!

• Thanks for this. Hmmm, I think 2 is best. 4 has incorrect doubling for 643, you doubled the bass so that one is not an option
– user35708
Commented Apr 27, 2022 at 16:09
• or number one actually
– user35708
Commented Apr 27, 2022 at 16:09