I'm going to stop analyzing bach's choral and try to analyze the keyboard partita, but it's so different from what it applies to choral, I don't know how to look at it.

I'm not asking what part of a song, but I want to know what theories should be based on when it's not a four-voice song as a whole.

What I am curious about is that in the keyboard partita, the 4 voices are not kept, and it can become a three-note chord and then a two-note chord.

In this process, the interval between each note is widened a lot (beyond the octave),

but In a 4-voice music, there is a rule that the spacing between the upper three voices must be maintained properly.

But is there no need for such a rule in keyboard partita?

Not to mention the keyboard partitas I'm looking at are full of wide spacing between notes. And there are a lot of skips with a big difference in pitch.

So... I don't know how to look and I can't even start the analysis.

  • Do you already understand the idea of chord tones and non-chord tones? Commented Sep 8, 2022 at 14:38
  • @michaelcurtis what do you mean?
    – guss2222
    Commented Sep 8, 2022 at 15:41
  • I don't know how else to ask. Do you know what those terms mean? Commented Sep 8, 2022 at 16:14
  • @michaelcurtis I know, i mean why are you asking that?
    – guss2222
    Commented Sep 8, 2022 at 16:20
  • When you account for non-chord tones and broken chord patterns and condense them to a harmonic outline the analysis should be simpler. I've tried to demonstrate in my answer. Commented Sep 8, 2022 at 18:49

3 Answers 3


You are conflating two different things: harmonic analysis, which for the most part is chord root analysis, and instrumental texture.

Assuming a context of C major, this...

enter image description here

...is fully voiced, four part, root position tonic chord.

But, even if you drop out some voices and omit the third and fifth of the chord, like this...

enter image description here

...or with a bit more context...

enter image description here

...labeling those incomplete chords with I to show they fulfill tonic chord function is OK.

...the 4 voices are not kept, and it can become a three-note chord and then a two-note chord...spacing between the upper three voices must be maintained properly...there are a lot of skips with a big difference in pitch

Those things are not chord root analysis. Some of it is about instrumental texture, balancing voices, interval clarity, some might fall under melodic analysis. In terms of analysis, those things are more like proofreading for errors. Stuff a teacher circles in red with comments like "tenor too low", or "you crossed voices", etc.

A lot of those things are connected to instrumental genre. The textures for choral, keyboard, and string music will vary. Don't expect all aspects of 4 part chorale texture to apply to other instrumental genres.

You probably won't see a leap of a ninth in the soprano of a 4 part chorale as you see in the treble part of this partita...

enter image description here

...but in this instrumental genre you should recognize that compound melody is very common and the passage would reduce to something like this...

enter image description here

Notice that I didn't label the Cm chord on beat two of the first bar. Depending on what level of harmony you want to analyze you can skip those details as various non-chord tone motions.

The beginning of the passage has some points where you could label additional chords (the parts boxed in red)...

enter image description here

You could add a bit more analysis details, like B♭: I V6 V7 I, but the harmonic essence of the first 4 bars to beat 1 of bar 5 is simply: tonic - dominant - tonic.

You don't necessarily need to do harmonic analysis on all the non-chord tone and broken chord figuration. Sometimes just labeling the principle cadences and key changes is all you need to get a useful structural analysis, an analysis of musical form.

Depending on the piece some melodic analysis may be helpful. Labeling things like sequential passages, development of melodic motifs, inversion of or imitation between parts, etc. can reveal the musical design.

I hope this helps you get started. Try analyzing more loosely than compared to a 4 part chorale. Think of it more as a sketch of harmonic analysis.

  • Thanks for the detailed reply. But it's late here right now, so I'll check later.
    – guss2222
    Commented Sep 8, 2022 at 16:35
  • In non-chord tones, it doesn't seem that different from a four-voice song in that it broadens the range of a certain chord. Of course, I appreciate the explanation, but that part was not what I was curious about.
    – guss2222
    Commented Sep 9, 2022 at 2:44
  • I was curious about the rest of what you explained, but it wasn't fully explained. As you said, free leaps, balancing voices, interval clarity (I'm not sure what this is. Are you talking about interval spacing?), etc. occur in keyboard partitas and other instrumental music, but why not in 4-voice songs? because the voice of each voice sound is 'different?' But if another instrumental music uses different instruments, shouldn't the same rules apply?
    – guss2222
    Commented Sep 9, 2022 at 2:44
  • What is your source for 4 voice music rules? Commented Sep 9, 2022 at 13:25
  • "But if another instrumental music uses different instruments, shouldn't the same rules apply?" No. But, again, you're really asking two different things: how to analyze the partitas, and why part writing for various instrumental genres differs. I think I answered the analysis one. I suggest asking a new question about the second. Although the glib answer is: I can play things on my piano (or whatever instrument) that no singer can sing, so you don't write parts the same way for various instruments including voice. Commented Sep 9, 2022 at 13:45

The 'rules' you have been used to following are for 4-part vocal writing.

Yes, keyboard is different. For a start it IS keyboard, not human voices!

Some of the Bach keyboard partita would fit into his collection of 2- and 3-part Inventions. Some are similar to the Preludes in 'the 48'.

So, how do you want to analyse them? Occasionally a chord-by-chord approach might be appropriate. More often I think you'll be talking about tonal centres and melodic/contrapuntal devices rather than trying to put a Roman Numeral harmony analysis under every note.

  • I'm just trying to see how the non-four note chords progress. But speaking more about the rules for voice spacing, can you tell me why the keyboard works and the voice doesn't?
    – guss2222
    Commented Sep 8, 2022 at 15:50

There’s a good reason to analyse two and three part piano pieces by Bach:

You learn a lot of harmonic progression and you can memorize the piece much easier.

I always do this when playing preludes, inventions or Suites.

Bach and other Barock composers in general begin with a cadence I-IV-V-I or i-ii-vii-i then he continues with a 5th fall sequence leading to the dominant key (first half of the piece). Thus it is quite easy to find the harmonic background of the music, of course you’ll find different soltions if you include diminished seventh chords …

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.