# Is this a hidden consecutive fifth?

I am working through some beginner counterpoint exercises, and I wrote this harmony above part of a cantus firmus:

.

By my understanding this should be a 3rd to a 5th, which should be acceptable, but when I played it in line with the rest of the piece, it didn't sound so great. Not that everything written in counterpoint should sound great, but I was wondering if it was a hidden consecutive fifth because the `C/A` kind of evoke a phantom `E` or `F` to complete the `F major triad` or the `a minor` triad, both of which would create a parallel fifth if present.

Can anyone shed a little light as to what might be going on here, or is my ear lying to me?

Here's my version of the example exercise taken from Chapter 1 of Fux's Counterpoint from which I ended up creating the aforesaid progression (my harmony on top, the cantus firmus below):

Restated: Is this a hidden consecutive fifth, and why or why not?

• What's the cantus firmus, especially at the last two beats of your second bar? If the cantus firmus is F-G there, you don't have a hidden consecutive fifth--you have a fully revealed consecutive fifth. (My first assumption is that the cantus firmus isn't in the passage and is in the unseen bass clef instead.) Oct 15, 2017 at 16:30
• @Dekkadeci The cantus firmus is the lower notes, my harmony is the notes in the higher voice. I am working out counterpoint in its most elementary form, with just two voices here. I think that answers your question. Oct 15, 2017 at 16:36

## 2 Answers

There are no hidden consecutive fifths.

Allow me to quote a little excerpt from Wikipedia:

The reason for avoiding parallel 5ths and 8ves has to do with the nature of counterpoint. The P8 and P5 are the most stable of intervals, and to link two voices through parallel motion at such intervals interferes with their independence much more than would parallel motion at 3rds or 6ths.

In this particular example the voices are moving in contrary motion and only one of the intervals is a perfect interval (minor third to perfect fifth), so there is no problem as far as the consecutive perfect intervals restriction is concerned.

• Which notes are you calling a diminished fifth? Oct 17, 2017 at 20:39
• I was calling a diminished fifth the B-F chord that I believed I saw. Thank you for pointing out my mistake, thankfully my answer holds and was updated to correct this detail. Oct 17, 2017 at 20:44
• Okay, thanks for the solid explanation as to why that progression isn't a hidden consecutive fifth. Oct 17, 2017 at 20:51

It's not a hidden fifth. The problem I think is that the two leaps D down to A then up to C# sound funny to me. Perhaps the last soprano note of bar 2 could be D which make allows the soprano to make a stepwise descent.

• Did you perhaps mean "the last soprano note of bar 2 could be B which would allow the soprano to make a stepwise descent?" Oct 15, 2017 at 17:05
• That's better that what I wrote. I actually meant the first note of the third bar. Either seems better than the actual example. I think what the OP is hearing is the jumpiness of the soprano rather than the fifth per se.
– ttw
Oct 15, 2017 at 17:12
• Oh, I see. Both of those would fix the problem it seems. (I am the OP, too, haha). I didn't realize that jumpiness in the Soprano would trigger my ear's better instincts, but that is nice to know. Oct 15, 2017 at 17:23