Wow. Thank you....I've been so perplexed by this piece!! Playing it over and over and trying to understand why it's so beautiful. Now I have an inkling as to why....but still a beautiful mystery.
Thank God I found this video. The others are not this detailed and they are prepared for advanced students. They use signs to explain things and advanced students get them. But I am a self learning student who started playing one year ago and less detail means no achievement for me. This video helps me a lot in the progress. Thank you so much. But I have a question: How is the C sharp is a dominant chord of a D chord at 7:20? I thought that we go five below to find the tonic of a dominant. So in this case, I thought the tonic of C# would be F# or F. Can you explain? Yes you explained it later in the video, but I still don't understand. I would be glad if you could be more specific or direct me to some sources. :)
It's the leading tone diminished chord. Let's say we are in the key of C for the sake of simplicity. There are two chords that create a strong pull towards the C major chord. One of them is the G7 chord (G B D F). The other is the Bdim chord (B D F). Notice something similar between these chords? They have 3 notes in common with each other (B D F). B is the leading tone, which creates a strong pull towards the tonic. F is a tritone away from the root of the chord, which makes the chord sound very unstable. Because of this instability and a strong pull towards the tonic, both of these chords have the dominant function. I guess this term is a bit confusing since dominant also refers to the 5th scale degree and the 7th chord built on that scale degree. But it's also a harmonic function. It basically means a chord with the strongest pull towards the tonic. And two chords in a key pull really strongly towards the tonic, and these are the dominant chord and the leading tone diminished chord. Both of them contain the leading tone, and both of them also contain the tritone (between the 7th and 4th scale degrees). But yes, to find the _dominant,_ you count 5 up from the tonic. But the dominant isn't the only chord with the _dominant function._ The leading tone diminished chord isn't _the dominant_ - it simply has a _dominant function_ because of its strong pull towards the tonic. (And as I said, G7 and Bdim behave in a similar way because they have so many common tones.) In this case, we are talking about the leading tone chord of Dm, the C#dim7. We can compare this to A7 (the dominant of Dm), and you'll notice that they have 3 common tones. A7 = A C# E G. C#dim7 = C# E G Bb. This is why both of them resolve so strongly to Dm (both contain the leading tone).
The answer by @MaggaraMarine could not have been more complete! Both the V7 and the VIIdim can function as dominants because of the presence of the leading tone and the tritone in them.
@@zmba6924 Glad the dominant function of the VIIdim chord makes sense! We will make a video only about dominants soon. To answer the last question, no, an F7 chord can't substitute a Dm. The F7 is a dominant chord and leads to a Bb chord; Dm is just a minor chord that doesn't lead anywhere (like dominants do). Was that the question?
Sure you can analyse this prelude harmonically - BUT you first should know that it is composed (technically) using counterpoint of 5 independent voices! For instance in the 2nd bar there is a suspension in the bass (c below d), followed by the solution into b (3 below d). Next bar suspension in the soprano: f is 7 above g, solution is e (6) above g ... and so on similar throughout the whole piece. Of course Bach "heard" the harmonies, but he had no grade theory nor the function theory, only "Generalbass" which works with intervals above a bass. Btw: also watch the progression of the bass ( and the melody)
Excellent analysis, but didn't JSB think in terms of Doe Rey Me instead of modern key signatures? And did he compose under the rules of this type of musical theoretical analysis, or did he simply write music which was a matter of pure beauty and genius? I'd appreciate a reply as my question is quite sincere.
Excellent points, let’s start with the first: 1) indeed Bach would not call musical notes A, B, C, but instead Do, Re, Mi. Until today, most countries in the world use that last system. But that does not change the notes, their pitch, or relationships, so any analysis using a different naming system still maintains the same underlying fundamentals. 2) music theory was very different in Bach’s time. They understood music in terms of voice leading, counterpoint, dissonance vs consonance, rather than dominant, subdominant, etc. These terms came around in the 1800s as a new way to understand how chords relate to each other. But still, the fundamental thinking is still the same: in Bach’s musical world, a G7 moving to C translates to the dissonances in the G7 chord (specifically the note B and F) resolving as consonances in the C chord (notes C and E). That resolution is just described in a different way today, when we say, for example, “dominant (G7) resolving in the tonic (C)” instead. But Bach was certainly well aware of the theory behind how music works. Such artist wouldn’t be thinking about theory, but instead was guided by it. His musical genious is better understood as how he was able to combine harmony rules and inspiration in art that is beautiful both in structural form and sound. Hope that makes sense!
This is the greatest insight on music theory I’ve had! So many great connections I’ve made in my mind and so much wisdom as to how each chord relates to one another. Thank you 🙏🏼
Thank you for the feedback and I am so happy the video helped you make these connections! Indeed, in tonal music chords are always moving towards one place or another, and being able to follow that movement is key to understanding how music works.
Ok, you explained us every chord, that G7 is the dominant of C, D7 is the dominat of G, C#dim is a substitute for A7 which is the dominant of dminor, Bdim is a substitute for G7, the dominant of C, C7 is the dominant of F, but you didn't explain us which function the F#dim chord has. Why? You just explained what Gounod did at this part in his compostion but you didn't explain the function of F#dim. I would suggest it's a substitute for the double dominant of C, which would be D7. I think thats why Bach can jump to Ab in the bass after it, which belongs to Bdim, because we can see Bdim as a substitute for G7 ( even with a flat 9) . Would you agree?
Excellent point, and yes: the F#dim is a secondary dominant, pointing to G (which is the dominant of the home key of C), but we move not to G but to Bdim (a substitute of the dominant G). Just keep in mind that Bach would not be thinking in these terms (dominant, tonic, etc) but in figured bass and counterpoint terms instead. When using the F# in the bass, Bach indicates that the bass should move towards the G. He simply delays that movement by going to the Ab instead. The Ab being the 7th in the Bdim chord would naturally move down to the G, which is why the whole sequence sounds so natural, and we move to G in the next measure.
This was awesome, hope you do more analysis of Bach pieces, I’m trying to learn more music theory and it’s cool to see Bach teaching how to modulate and using substitutions through this
Thank you. What a welcome and detailed analysis. Unfortunately the piano made it difficult to hear your voice in some cases. But I will listen again to try to pick up more.
Wonderful tutorial; includes the chord notation, the piano, and the commentary. Your piano has a beautiful tone. The challenge I have is that the volume of the piano obscures the commentary along with it until you've stopped playing. Thanks for the great work
I would love to understand music like this, please help. I've been learning piano for a couple years now and I can read sheet music, play chords, scales, fingering etc, all at a reasonably "beginner" stage of course. But I would like to understand the "language" of music, I feel it would be much easier to learn a piece, when you know why you're playing what you're playing in terms of the relationship between chord etc.. rather than just playing what you see on the page until you get it through muscle memory. I want to know tonic, dominant, and terms like these so I know what and why I'm playing what I am playing. What do I need to learn?
you explained all that in one go, very good i didn't realize the dminor at the end, interesting d minor is in the beginning as well in the 2nd chords, didn't notice that till you pointed it out
Thank you for the feedback! Measure 12 has G in the bass (the lowest note is the bass, regardless if it is in the right or left hand). So we have a chord with G-Bb-E-C#. Now to find the root of this chord we need to order these notes where each note is a skip (also referred to as a 3rd) above the other. As it is, G to Bb is a skip (3rd), but Bb to E isn't, so the G cannot be the root. The only correct order is C#-E-G-Bb. Now we know the C# is the root, so this is a C# chord. The type (diminished) comes from the intervals each note creates with the bass. 1) the first interval is the minor 3rd C# to E, 2) the second interval is a diminished 5th C# to G, 3) and the last interval is a diminished 7th C# to Bb. A chord with a minor 3rd and a diminished 5th is called a diminished chord; add the diminished 7th and we have a "fully" diminished chord. So this is a C# fully diminished chord.
Absolutely, that measure was added by editors to “fix” the missing measure where the bass moved from an F# to the Ab (which based on the rules of counterpoint is indeed a very strange movement), by adding the measure in the middle with the G in the bass. But Bach’s own manuscript doesn’t have this measure so I would certainly not play it.
Thanks! Maybe this question has been made, but why there is always the silence symbol marked after the first note of each measure if we are playing the left hand legato?
That is a great question! Bach did not think of this music as a sequence of notes moving from the left hand to right hand, but instead a 5-part choral where each voice is coming in one after the other (that is why we see those rests). It is a subtle difference that highlights the chordal progression of this music, rather than a melodic one.
Excellent, but could you do it again with a good microphone and without pedal, so that we could hear what you are saying? I'd really appreciate. Thank you very much.
I agree: When you speak, your nice explanations should take the foreground and everything else should be a very soft and unobtrusive background. YOU should take the spotlight at center stage ;-)
Measure 21 comes two measures after the arrival in the C major key (after we spent a few measures in G major), so this Fmaj7 is the IV in the key of C. Another hint that this F is not a tonic chord comes from the presence of the 7th in this chord (F-A-C-E, where E is the 7th above the bass F). In this period composers would never play a tonic chord with the major 7th.
Hey there! Both are correct. Bach wrote this prelude without that extra G chord. Although some musicians say the bass moving a dimished third (from F# to Ab) is a very strange move, it is exactly what Bach wrote and intended. Gounod comes along over 100 years later and uses this prelude as an accompaniment for his Ave Maria. He added the G chord between those measure to better fit his melody. So if you are playing Gounod’s Ave Maria, you should play it with that extra measure. If you are playing Bach’s prelude, you should not play it.
Thank you for providing this excellent analysis of this piece and its harmonies. I am starting to study the work and your video has really improved my understanding of it.
So glad to know that! This progression wasn’t invented by him, it actually around even before. The one important difference is that a jazz progression will typically add a 7th to all chords, including the tonic at the end, making it a ii7-V7-I7; and Bach would had used ii7-V7-I. He would never end a phrase with a 7th chord, something jazz composers have no problem with. In Bach’s time composers were very much concerned with balance and stability in harmony. A 7th chord is unstable (due to the dissonance of the 7th), so ending a piece with such chord would had been a very strange thing to do in his time. Such concerns were thrown out the window in the late 1800s, so jazz composers in the 20th century were more concerned with color and pure sound, rather than stability and order.
