I am harmonizing a Mozart soprano melody with a musical friend. Now, I could scour the internet for a week trying to figure this out, but I figured I would instead ask the music.stackexchange Gods first to greater effect.
I am having trouble wrapping my brain around counterpoint dissonance handling, specifically in the correct designation of “strong” and “weak” beats.
This is where I am so far with the harmonization. In second species counterpoint, you have two half notes per measure, and the second half note can hold a dissonance. Now, this piece is in 4/4, but if the chord changes are occurring twice per measure, beat 3 there could theoretically hold a dissonance? Measure 2 changes chords twice like this. (Note that there is no dissonance in this measure but I'm bringing it up to compare it with measure 4.)
In the 4th measure, you have chord changes that are occurring on the 3rd and 4th beat. Please notice that I do indeed have a dissonance on beat 3 and this is where I'm lost...
Now, if this is 3rd species, where there are 4 beats in a measure, the 3rd beat is strong(ish) and not fitting for a dissonance.
So measure 4's dissonance on beat 3 is correct in 2nd species, but wrong in 3rd?
Can individual measures be treated as quadruple meter and some in duple depending on the chord changes?
Can someone provide me some insight?
Thanks to Heather S. and some reading I've been doing, I think I've come up with my own answer to this problem.
Now, what I didn't realize before and what I realize now is that there are two aspects to this whole "strong beat/weak beat" issue.
1. Strength/weakness as related to the meter of the piece/measure.
Ex: 4/4: First and 3rd beats are strong. 2/4: First beat is strong etc.
2. Strength/weakness as related to note(s) against a note in different ratios.
Ex: 2 notes against 1: first note is strong, 4 notes against 1: first and 3rd notes are strong etc.
This has helped me to understand the issue, because I wasn't able to separate the two aspects previously.
Now, I also believe I have the answer to best applying these ideas...
In Alfred Mann's intro in his translation of Fux's Gradus Ad Parnassum, he basically spells out one of the main goals of counterpoint: balance.
So, whatever you choose to do in terms of applying dissonance in meter and note-against-note situations, your main goal is creating balance in your music.
Thanks for all who helped.!
Edit for Michael:
Michael thank you again for your responses!
Please take this image for example:
I have altered some things in the first few measures to better help explain my point.
For starters, I know a first inversion tonic chord is poorly placed so early, but I only did it for the sake of allowing a passing 6/4 V chord.
Now, looking at the bass voice: if we pretend there is an invisible cantus firmus present in measure 2 as tonic note C, then we can see how a 2:1 dissonance on "beat 3" works - it is a dissonance that resolves in the same direction by step. It also justifies common theory about proper placement of dissonant chords like the passing 6/4. Notice I put beat 3 in quotes a moment ago: If this was duple meter, then this would be beat 2; I feel the chord change here makes this segment act like duple meter justifying 2nd species 2:1.
Now, applying this "invisible whole note cantus" over measures justifies what many theorists say about dissonant chords over the bass (ex: passing 6/4 on weak beat.) The voices show respect the bass, and the bass shows respect to the the invisible cantus.
However, with that logic, we are already in some sort of contradiction here: Because beat 3's bass note places the melody in error with species 2 - a 4th above the bass that does not resolve by step. It leaping down to the D correctly makes a proper leap to a consonance in regard to the prevailing chord, but, if looking at the bass voice, we see a dissonance being leapt away from.
Perhaps this is a better example:
Here the 4th above the bass never resolves down - it is instead the movement of the bass that provides the resolution - calling into question where/what the true cantus is.
It seems as though two schools of thought are meeting in this thread.
Do you see how all of this is making my brain leak out my ears?? :)