Last section, we talked about cadential 6/4 chords, which are I 6/4 chords that precede a root position dominant triad, usually at a cadence. Even though this I 6/4 chord has tonic harmonies, it actually has a dominant function, because its bass is the dominant scale degree, and its upper voices quickly resolve to the dominant. In other words, even though the I 6/4 chord is technically a chord, it is not used to build a harmony. Rather, it is used as an embellishment to the dominant harmony that follows it.
The reason why 6/4 chords are usually used as embellishments is because they are generally weak chords. If you have a keyboard or piano near you, consider playing a I chord in C Major. Now, invert the chord so that you’re still playing a I chord, but it is in second inversion, i.e. a I 6/4 chord. You will probably notice that the tonic quality of the C Major chord is far less prominent. Similarly, a V 6/4 chord doesn’t really sound like a dominant chord, and a IV 6/4 chord doesn’t really sound like a subdominant chord.
Aside from cadential 6/4 chords, we usually see 6/4 chords in three other contexts: neighboring or pedal 6/4 chords, passing 6/4 chords, and arpeggiated 6/4 chords. We’ll go through each of these types of 6/4 chords one by one, and learn what they are and how to write them using proper voice leading.
Neighboring or Pedal 6/4 Chords
The pedal 6/4 chord, also called the neighboring 6/4 chord, occurs when the third and fifth of a root-position triad are embellished by upper neighbor tones while the bass line stays the same.
For example, suppose that we are in Ab Major and we want to embellish two root position I chords using a pedal 6/4 chord. Since the bass must remain the same for all three chords, we have to choose a IV chord for our passing 6/4 chord. This is because the bass of the root position tonic triad in Ab Major is Ab, and the bass of the second inversion IV chord, the IV 6/4 chord, in Ab Major is also Ab.
Next, we write the chord progression such that the upper voices in the I chord move up to spell the IV 6/4 chord. In this case, the upper voices of the I chord would be C and Eb, and the upper voices of the pedal 6/4 chord would be Db and F.
Here is an example of a pedal 6/4 chord in C Major:
Passing 6/4 Chords
In music, a passing tone is a musical note or chord that is played or sung briefly as a transition between two other notes or chords in a melody or harmony. It is typically used to create a sense of movement or tension and release in a piece of music. Passing tones can be diatonic or chromatic, meaning they come from within the key or scale being used, or they can come from outside of it.
A passing tone is a type of non-chord tone. As we have seen before, a non-chord tone is a musical note or tone that is played or sung in a melody or harmony that does not belong to the chord that is currently being played. Non-chord tones can be dissonant or dissonant-sounding and can be used to create tension and dissonance in a piece of music.
That being said, you can harmonize a non-chord tone without having the chord associated with the non-chord tone be a part of the chord progression. This sounds a little confusing – doesn’t a chord in a chord progression have to be part of the chord progression, by definition? Well, yes and no. When I say that the chord isn’t part of the chord progression, I mean that it doesn’t add any harmonic value to the piece. Let’s consider an example:
Say you are in the tonic section of a phrase, and you have a I chord followed by a I6 chord. What does the bass line look like? You will have the tonic followed by the mediant. If you want to add some melodic interest to the bass line, you might consider adding the supertonic in between the tonic and the submediant, so that you have a nice stepwise melody. You’ve just added a passing tone in the bass line.
But perhaps you want to go a little further than that, and add notes in the other voices that blend well with this melody in the bass line. Of course, you could insert a ii chord or a vii6 chord in between these notes, but the ii chord has a strong predominant function, and the vii6 chord has a really strong dominant function. It would sound pretty weird to go from a tonic chord to a predominant chord back to a tonic chord, and although vii6 chords can be used as pedal tones between two I chords, as we’ve seen earlier, you’re not looking for such a strong chord. You’re looking for a weak chord that clearly doesn’t add to the harmonic progression. Your other option is to add a V 6/4 chord between the tonic chords. This is a passing 6/4 chord.
Any type of 6/4 chords are weak, meaning that they don’t really sound like the chord defined by their root. In other words, inserting a V 6/4 chord in between the two tonic chords won’t really sound like a tonic-dominant-tonic progression. It will just sound like a tonic chord, some other notes, and then another tonic chord. The benefit to this approach is that you will keep a strong tonic harmony while still adding melodic interest to the piece.
Let’s see what this looks like in practice:
Here, we are in Eb Major, and we see a I-V 6/4-I6 progression in the first three chords of the passage. This gives us an ascending stepwise melody (Eb-F-G) in the bass line.
Voice Leading with Passing 6/4 Chords
Let’s talk about voice leading with passing 6/4 chords. Firstly, the 6/4 chord should almost always appear on a weak beat in the measure. In this case, where we are in 4/4 time and we are using quarter notes, the V 6/4 chord occurs on the second beat, which is weaker than the first and third beats, where the tonic chords are written.
Second, the upper voices should move stepwise when voice leading into and out of the passing 6/4 chord. Notice how in this example, the soprano voice moves down stepwise, mirroring the bass line. If you can achieve this while maintaining our other voice leading rules, then you will create a beautiful voice exchange between the soprano and bass lines, and your music will sound really nice.
Arpeggiated 6/4 Chords
Finally, let’s talk about arpeggiated 6/4 chords. An arpeggio is a type of broken chord where the notes of a chord are played in a sequence. For example, an ascending C Major arpeggio will be C-E-G, and a descending C Major arpeggio would be G-E-C. You can invert arpeggios just like you do with chords. However, arpeggios are usually ascending or descending. For example, you wouldn’t play E-G-C such that E is a lower note than G but C is lower than E and G.
We can use 6/4 chords to harmonize arpeggios in the bass line. For example, you might write a I chord followed by a I6 chord, so the bass line goes from the tonic to the mediant. To complete the arpeggio, you might write a I 6/4 chord, so the bass line has a tonic-mediant-dominant melody. It is good practice to sustain the upper voices when writing arpeggiated 6/4 chords – meaning that the upper voices should stay the same and not jump around. We will usually write the 6/4 chord on a weak beat.
Here is an example:
Sometimes, we will just have a I chord followed by a I 6/4 chord. This is quite common in waltzes, which are pieces written in 3/4 time. Waltzes usually have a strong downbeat and two lighter upbeats, so we might have a I chord on the downbeat followed by two I 6/4 chords on the upbeats.
Note that while arpeggiated 6/4 chords don’t have to be written with the I chord, they usually are. It is also common to see arpeggiated V 6/4 chords. However, it is rare to see these written on other diatonic chords, although you might still see them occasionally.
Other Voice Leading Rules There are some final voice leading rules to sum up this section. Good news: after this you’re almost done with voice leading. You’ll learn some new melodic techniques and new ways to interpret chords, but there will be less rules in the coming units. Hang in there – you got this!
First, you should note that there are some unacceptable chord progressions that you should avoid. They are:
- V-IV
- V-ii
- Ii-iii
- IV-iii
- ii-I
- V-vi6
- and iii-viio
If you’re wondering why this is the case, consider the T-PD-D-T phrase we discussed earlier. All of these chord progressions are moving backwards in this progression, resulting in poor voice leading.
Finally, there are some chords that you should just avoid completely. They are root position viio chords, vi6 chords, and iii6 chords. You might see the latter two when you learn about modulation in Unit 7. However, they are rare and you should try not to use them when writing your own chord progressions. Also, if you are realizing a figured bass and you come across these chords, make sure to check your work! They usually won’t appear on this section of the AP Exam.
Frequently Asked Questions
What's the difference between a passing six-four chord and a pedal six-four chord?
A passing 6-4 and a pedal (neighboring) 6-4 look similar on paper but behave differently in the bass and upper voices. - Passing 6-4 (PIT-2.L.2; PIT-4.F.1): the bass moves stepwise (it's the middle note of a three-note passing figure), so the 6-4 chord harmonizes a bass passing tone. Upper voices typically move by step as well, and you should double the fifth of the 6-4. It usually falls on a weak beat. - Pedal (neighboring) 6-4 (PIT-2.L.1; PIT-4.F.2): the bass stays stationary (a pedal), while the third and fifth of the root-position triad are embellished by their upper neighbor tones. Upper voices move to neighbors while the bass holds; the 6-4 also usually falls on a weak beat. Remember cadential 6-4s are different (on a strong beat resolving to V). Review the CED bullets above and check the Topic 5.7 study guide for examples (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ). For more practice, hit the unit page (https://library.fiveable.me/music-theory/unit-5) or the practice bank (https://library.fiveable.me/practice/music-theory).
How do I know when to use a neighboring six-four versus an arpeggiated six-four in my composition?
Use the musical situation to choose: if the bass stays on the root while the upper voices move into their upper neighbor tones (embellishing the triad’s 3rd and 5th), you’re writing a neighboring (pedal) 6/4—it usually falls on a weak beat and functions as a brief embellishment (CED PIT-2.L.1, PIT-4.F.2). If the bass is arpeggiating the same triad (or oscillating between root and fifth) while the three upper voices hold a static chord, you’re writing an arpeggiated 6/4—again generally on a weak beat except in special textures (CED PIT-2.L.3, PIT-4.F.3). Also remember passing 6/4 harmonizes a bass passing tone (CED PIT-2.L.2)—don’t confuse that with the other two. For AP part-writing, keep voices stepwise for passing/neighbor 6/4, double the fifth in passing 6/4, and ensure proper doubling/voice-leading in arpeggiated cases (CED PIT-4.F.1–F.4). Review examples in the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and practice lots of exercises (https://library.fiveable.me/practice/music-theory).
I'm confused about doubling rules - why do you double the fifth in passing six-four chords but not in other types?
Good question—the rule comes from how a passing 6-4 functions. A passing 6-4 is just a brief embellishment of a root-position triad that harmonizes a bass passing tone (CED: PIT-2.L.2). Because it’s transient and all voices should move by step (PIT-4.F.1), you double the fifth so the other voices can move smoothly in stepwise motion and the chord reads clearly as an embellishment of the underlying root. Doubling the third would either (a) force awkward leaps or parallel problems when the voices resolve, or (b) double a more active chord tone (the third) that can create voice-leading conflicts. Neighboring/pedal and arpeggiated 6-4s have different functions (bass stationary or arpeggiated) so you follow their specific conventions instead (PIT-2.L.1, PIT-2.L.3). For more examples and practice, see the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and Unit 5 review (https://library.fiveable.me/music-theory/unit-5).
What does it mean when the bass "arpeggiates a complete triad" in arpeggiated six-four chords?
It means the bass line is outlining (playing) all three notes of the root-position triad in succession while the three upper voices hold a static chord. In an arpeggiated 6–4 the upper voices stay on the chord tones (usually sounding the triad above the bass), and the bass moves stepwise or by leaps through root → third → fifth (or some order that completes the triad). Because the upper voices don’t change, those bass notes temporarily create 6–4 sonorities against the static upper chord tones (that’s why we call it an arpeggiated 6–4). For AP tasks, recognize this by seeing only the bass move through a triad while upper parts are stationary (CED PIT-2.L.3 and PIT-4.F.3). Want more examples and practice? See the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ), the Unit 5 overview (https://library.fiveable.me/music-theory/unit-5), and try problems at (https://library.fiveable.me/practice/music-theory).
How do I identify which type of six-four chord I'm hearing in a listening example?
Listen for three things: where it falls in the meter (strong vs weak beat), what the bass is doing, and how the upper voices move. - Cadential 6-4: on a strong beat, the bass usually holds scale-degree 1 while the upper voices form 6–4 above it and then resolve to V (the 6 and 4 both resolve down to 5 and 3). If you hear a big arrival that immediately becomes V, it’s cadential (CED: cadential 6-4 occurs on strong beats). - Passing 6-4: on a weak beat, the bass is a stepwise passing tone (moves step up or down), upper voices move mostly by step, and the 6-4 harmonizes that passing bass note. In writing, the fifth is commonly doubled (PIT-4.F.1). - Neighboring/pedal 6-4: bass stays stationary (pedal), the third and fifth of the root triad are embellished by upper neighbor tones; usually on a weak beat (PIT-2.L.1; PIT-4.F.2). - Arpeggiated 6-4: bass arpeggiates the triad (or alternates root and fifth) while the three upper voices stay static (PIT-2.L.3; PIT-4.F.3). On the exam, mark meter placement and immediate harmonic motion (does it go to V?)—that’s usually enough to ID the type. For more examples and practice, see the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ), the Unit 5 overview (https://library.fiveable.me/music-theory/unit-5), and AP-style practice problems (https://library.fiveable.me/practice/music-theory).
Can someone explain why passing and neighboring six-fours go on weak beats but cadential six-fours go on strong beats?
Short answer: because function and rhythm go together—passing and neighboring 6–4s are nonharmonic embellishments so they belong on weak beats; the cadential 6–4 is a structural harmony (a decorated V) so it belongs on a strong beat. Why: PIT-2.L.1–2 say neighboring/pedal and passing 6–4s are embellishments of a root-position triad or a bass passing tone. They fill in stepwise motion and usually occur on weak beats so they don’t sound like new structural harmonies. By contrast the cadential 6–4 (CED PIT-4.F.4) acts as a harmonic preparation for V: the 6–4 intervals are treated as part of the dominant sonority and must fall on a strong beat so the arrival on V feels decisive. On the AP exam you should label passing/neighboring 6–4s as weak-beat embellishments and cadential 6–4s as strong-beat cadential harmony (see the Topic 5.7 study guide for examples: https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ). For extra practice try Unit 5 problems (https://library.fiveable.me/music-theory/unit-5) or the practice set (https://library.fiveable.me/practice/music-theory).
I don't understand the voice leading rules for pedal six-four chords - what stays the same and what moves?
For a pedal (neighboring) 6–4, the bass stays absolutely stationary—that’s the defining trait. The upper voices: the third and fifth of the underlying root-position triad move by step to their upper neighbor tones and then return, so you’ll usually see stepwise motion in the upper three voices while the bass holds the root (CED PIT-2.L.1 and PIT-4.F.2). These 6–4s normally sit on a weak beat and function as an embellishment of a root-position triad, not as a separate harmony. Contrast that with cadential 6–4 (on a strong beat) which resolves to V. On the AP exam you’ll be asked to identify and write these in part-writing and harmonic dictation—follow the bass stationary rule, keep upper-voice motion stepwise, and place the pedal 6–4 on a weak beat (see the Topic 5.7 study guide: https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ). For more practice, try problems in Unit 5 (https://library.fiveable.me/music-theory/unit-5) or the 1,000+ practice items (https://library.fiveable.me/practice/music-theory).
What are some common mistakes to avoid when writing passing six-four chords in four-part harmony?
Common mistakes when writing passing 6–4s (PIT-2.L.2; PIT-4.F.1): - Placing the 6–4 on a strong beat. A passing 6–4 should fall on a weak beat as it harmonizes a bass passing tone. - Not doubling the fifth. AP voice-leading conventions require the fifth of the 6–4 to be doubled. - Using leaps in the upper voices. All voices (especially the three upper parts) should move by step through a passing 6–4. - Creating parallels or hidden/direct perfects. Stepwise motion helps avoid parallel fifths/octaves and forbidden direct outer-voice perfects. - Leaving out chord tones or omitting required notes. Inverted triads and 6–4s must be spelled correctly and usually complete in four parts. - Writing the 6–4 in an implausible harmonic context (e.g., on a strong beat or followed by poor chord successions). For guided examples and practice problems that match the CED, see the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and Unit 5 resources (https://library.fiveable.me/music-theory/unit-5). For extra drills, try the practice set (https://library.fiveable.me/practice/music-theory).
How do I analyze a piece of music to find examples of different types of six-four chords for my portfolio?
Start by scanning the score for where a root-position triad’s 3rd and 5th are sounded above a bass that makes the chord look like a 6-4 (two voices a 6th and a 4th above the bass). Then classify using CED criteria: - Neighboring (pedal) 6-4: bass stays stationary; the 3rd and 5th are embellished by upper neighbor tones; usually on a weak beat (PIT-2.L.1, PIT-4.F.2). - Passing 6-4: harmonizes a bass passing tone (bass moves stepwise through scale); upper voices move by step; double the 5th when writing (PIT-2.L.2, PIT-4.F.1). - Arpeggiated 6-4: bass arpeggiates the same triad while the three upper voices are static (PIT-2.L.3, PIT-4.F.3). - Cadential 6-4 (important for exam): occurs on a strong beat and resolves to V (PIT-4.F.4). For your portfolio: pick 2–3 clear examples of each type, notate bar numbers, show the bass motion and voice-leading, and explain why it fits the CED definitions. Use the Topic 5.7 study guide for refresher examples (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ), review Unit 5 overview (https://library.fiveable.me/music-theory/unit-5), and practice ID with problems (https://library.fiveable.me/practice/music-theory).
Why does my arpeggiated six-four sound wrong when I move the upper voices instead of keeping them stationary?
Because an arpeggiated 6–4 is defined by the bass moving while the three upper voices stay static, moving those upper voices changes the harmony and the expected voice-leading. If you move the upper voices you: - stop sounding a static triad in the upper parts (so it’s no longer an arpeggiated 6–4 per PIT-2.L.3 / PIT-4.F.3), - often create stepwise/nonstepwise motion that implies a passing or neighboring 6–4 (PIT-2.L.1–2) or a different chord entirely, and - can introduce parallel perfects, unresolved tendency tones, or bad doublings that make the progression feel “wrong.” So if you want the characteristic arpeggiated-6–4 color, keep the three upper voices stationary and let the bass arpeggiate the triad (or alternate root and fifth). For practice and examples, review Topic 5.7 (study guide: https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and try AP-style part-writing problems in the Unit 5 practice set (https://library.fiveable.me/music-theory/unit-5 and https://library.fiveable.me/practice/music-theory).
What's the difference between upper neighbor tones and passing tones in six-four chord contexts?
Upper neighbor (pedal) 6-4 vs passing 6-4 comes down to which note is the nonchord tone and how voices move. In a neighboring (pedal) 6-4 the bass stays stationary on the root while the third and fifth of the triad are each embellished by upper-voice upper neighbor tones—upper voices move to neighbor tones and back (bass static, weak-beat placement) (CED PIT-2.L.1, PIT-4.F.2). In a passing 6-4 the bass itself is a passing tone (middle note of a three-note step in the bass); the 6-4 chord simply harmonizes that bass passing tone and all voices usually move stepwise (weak beat; double the fifth in part-writing) (CED PIT-2.L.2, PIT-4.F.1). Remember cadential 6-4 is different (on a strong beat resolving to V). For examples and AP-style practice, see the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and Unit 5 review (https://library.fiveable.me/music-theory/unit-5).
I'm working on a composition project - when would I choose an arpeggiated six-four over other types?
Pick an arpeggiated 6–4 when you want motion in the bass that doesn’t change the upper sonority—i.e., the upper three voices stay on a static triad while the bass arpeggiates that same triad (or flips between root and fifth). Use it when you want bass-driven momentum (waltz/march accompaniments, arpeggiated textures) but don’t want to imply a new harmony in the upper voices. In practice: keep the upper voices stationary, let the bass outline the triad by step or leap (PIT-4.F.3). Unlike passing or neighboring 6–4s (which occur on weak beats and require stepwise voice motion or neighbor tones), the arpeggiated 6–4’s identity comes from bass arpeggiation. Also follow AP voice-leading conventions: avoid creating poor chord successions and double appropriately when writing the full texture (see PIT-4.F guidance). For more examples and practice, check the Topic 5.7 study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ), the Unit 5 overview (https://library.fiveable.me/music-theory/unit-5), and practice questions (https://library.fiveable.me/practice/music-theory).
How do I fix voice leading errors in my six-four chord progressions for my AP exam?
Quick checklist to fix 6-4 voice-leading errors on the AP exam: 1) Identify which 6-4 it is. Cadential 6-4 belongs on a strong beat and resolves to V (the 6→5 and 4→3 in the upper voices). Passing 6-4 sits on a weak beat, all voices move stepwise, and you should double the fifth. Pedal/neighbor 6-4 has a stationary bass with upper neighbors. Arpeggiated 6-4 = static upper three voices, only bass moves (CED PIT-2.L & PIT-4.F). (See the Topic 5.7 study guide: https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) 2) Fix typical errors: avoid parallel 5ths/octaves (DCVLE), don’t double the wrong chord tone (passing 6-4: double the fifth), resolve the 6th/4th properly when cadential, and keep upper-voice motion primarily stepwise for passing/neighbor 6-4s (CED PIT-4.F.1–3). 3) Practical edit: rewrite offending voices so outer voices don’t move in similar leap into a perfect interval, change a doubling if needed, and check metrical placement (weak beat for passing/pedal; strong for cadential). On the exam, part-writing (Figured Bass / Roman numerals) will mark these errors in voice-leading scoring—so practice the three types and use the Unit 5 review and 1000+ practice problems (https://library.fiveable.me/music-theory/unit-5 and https://library.fiveable.me/practice/music-theory).
What does "harmonizes a bass passing tone" actually mean in simple terms?
“Harmonizes a bass passing tone” just means the chord you hear is built to fit a short stepwise note in the bass that moves between two stable notes. In plain terms: the bass goes A → B → C (or C → B → A) and the middle note (B) is a passing tone—not a new harmony goal, just a connector. The passing 6-4 is the specific chord that occurs when the upper voices form a 6-4 sonority while the bass is on that middle passing note. It usually falls on a weak beat and the other voices move by step to keep the motion smooth (CED: PIT-2.L.2 and PIT-4.F.1). On the exam you should expect passing 6-4s to have stepwise voice-leading and the fifth doubled when you write them (CED: PIT-4.F.1). For more examples and practice, check the topic study guide (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and hit the 1000+ practice problems (https://library.fiveable.me/practice/music-theory).
Can you give me examples of pieces that use neighboring six-four chords so I can hear how they sound?
Good question—the easiest way to “hear” a neighboring (pedal) 6–4 is to listen for a stationary bass (usually tonic) while the upper voices briefly move to upper-neighbor tones, creating a 6–4 sonority on a weak beat before returning to the original chord. Where to listen: - Bach’s four-part chorales (recorded collections or any Bach chorale anthology). Many chorales show clear pedal/neighbor 6–4s: follow the score and watch for the bass holding while soprano/alto move stepwise to neighbors. - Classical homophonic works by Mozart and Haydn (slow or accompanying passages). Their piano sonatas and string-quartet accompaniments often use neighboring 6–4s as light embellishment on weak beats. - Beethoven piano sonatas and Classical cadential passages for contrast—you’ll also hear cadential 6–4s (on strong beats resolving to V), which helps you distinguish types. How to practice for the AP exam: - While listening, score-read and label any 6–4 you find using CED rules (PIT-2.L.1: bass stationary, upper voices move to upper neighbors; occurs on weak beat). That trains both aural and notated identification (PIT-4.F). - Use the Topic 5.7 study guide for guided examples and analysis (https://library.fiveable.me/music-theory/unit-5/additional-64-chords/study-guide/Qh3LHV4QTvf36VrCMEpQ) and drill with 1000+ practice problems (https://library.fiveable.me/practice/music-theory). If you want, tell me one Bach chorale or a Mozart sonata movement you have access to and I’ll point to likely measures to inspect in the score so you can hear the exact neighboring 6–4 in context.