Applications of Half Diminished Seventh

In a recent article, I explained the concept of the half diminished seventh chords. Additionally, in the summary section , I introduced that the seventh chord version of it is also referred to as “Half Diminished Seventh”.

However, in the introduction, I covered only one instance where the VII was taken as the root. Here, I will now introduce several other non-diatonic applications of the half diminished seventh chord.

1. IIø7 : Parallel Minor Melancholy

The first one is II₇, composed of re, fa, la♭ and do.

Having a flat on la, it can be considered as one of the parallel minor chords.

So when you play phrases on this chord, mi and ti may also involve flats, if you want them to.

In terms of sonority, it has similarity to IV_m as it shares the characterful la♭ tone, bringing a melancholic mood. Similar to how the IVm can be introduced through the substitution of the IV, the IIø7 can be placed in locations where the IIm would traditionally gom, and typically goes 5_▼ to V chords.

IV_Δ7III_m7II_m7V₇I

IV_Δ7III_m7II₇V₇I

The upper one is a progression played normally as 4-3-2-5-1. In contrast, the lower one has IIm7 replaced by IIø7. The difference is subtle, but please the presence of la♭ creates the distinctive atmosphere characteristic of parallel minor.

2. IIIø7 : Deep Sinking

VII₇ attaches just before III₇, the ace of the secondary dominant, reinforcing the overall emotional flow. Similarly, there is a classic pattern of placing III₇ just before VI₇.

Compared to the regular mi–so–ti–re chord, the addition of a flat to ti introduces an even deeper sense of sinking emotion. It can be easily incorporated into a 4-5-3-6 type progression.

II_m7V₇III₇VI₇II_m7IV_mI

That’s the vibe! There’s a profound depth when transitioning to the third chord. This flavor is undoubtedly unique to half diminished chords. How does it feel when, for example, it’s III₇, a chord we’re already familiar with?

II_m7V₇III₇VI₇II_m7IV_mI

As this involves a sharp alteration, there’s a distinct sense of “heightened excitement,” and the musical mood achieved is entirely different from III₇. Choose between them based on the desired expression.

Example

“心の瞳” (Kokoro no Hitomi, The Eyes of the Heart) is a famous Japanese pop song by Kyu Sakamoto, covered by many musicians. Personally, the best Japanese ballad ever written.

Listen to the chorus part(1:32-). The part involves many advanced chords just explained in this chapter, but listen to how the part ends; from 2:09- it uses the progression VV_7/7III₇VI₇II_m7V₇I. What a beautiful moment!!

VV_7/7III₇VI₇

The lyrics here is also excellent, it’s saying “Even if time steals our youth, our hearts will forever be connected by an unwavering bond.” It’s a genuine love song and the highly deep emotional III₇→VI₇ is the perfect-fit here.

IIIø7, though not frequently used, has a great potential in creating heart-startling progressions.

3. ♯IVø7 : Emotional Arousal

Finally, let me introduce IV₇. It’s a somewhat unique chord with an accidental sharp on the root. In terms of progressions, the common patterns involve descending to the adjacent IV or ascending to V.

IV₇IVIII_m7VI_m

In terms of constituent tones, raising the root of IV_Δ7 by a half step results in this chord. Therefore, the motion IV₇→IV_Δ7 creates a smooth motion with the root descending by just a half step. This imparts a very unique auditory impression, as if the elevated emotions gently settle down.

Examples

The second part of “I Wanna Be Where You Are” starts with 4-3-6 progression. After repeating it three times, it goes to IV₇IV_Δ7III_m7.
This chord, with its root just a half-step higher compared to IV_Δ7, often appears in the position where IV_Δ7 was originally present, as a substitute in the latter part of the musical story. By using this way the the half-step difference becomes more prominent, contributing to an elevated sense of excitement in the music.

“Virtual Insanity” by Jamiroquai is a good example. It loops the progression VI_m7II₉V₉I_Δ7IV₇IV_Δ7III₊₇VI_m7. The half-diminished chord inserted in the middle section clearly enhances the unsettling atmosphere of this song.

Rootless Voicings

♯IVø7 consists of fa♯, la, do and mi. This is quite similar to the chord tones of II₉.

The difference lies solely in whether re is included or not. Therefore, these two share some sonic similarities, and as a result, ♯IVø7 may progress to V just like II7 does, or it may also progress to II7.

Examples

The chorus part of “Seven Days” by Sting starts with IV_Δ7IV₇VIII_7/3VI_m.

In such cases, even though re is absent, there is a significant resemblance in meaning to the secondary dominant II₉. Therefore, in analysis (especially in classical theory), this is often considered as “essentially a II chord with the root accidentally missing”, and is called a Rootless Voicing.

So if someone were to ask about the root note of this ♯IVø7, theoretically, answering re could be considered correct in some schools of theory. It may seem strange that a note that is not present is the basis of the harmony! However, understanding this unexpected similarity with other chords is crucial.

But beware that not all ♯IVø7 chords are unconditionally considered as the rootless form of II9. This categorization applies to only some instances when analyzed comprehensively, taking into account factors such as contexts, melody and so on.
The “rootless chords” can appear in other situations too, which is covered in Chapter IV.

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Whichever note is set as the root, the half-diminished chords bring significant tension to the music due to the instability created by the tritone interval between the Rt and the flattened 5^th. Mastering the use of these complex sounds, not achievable with just major/minor chords alone, is the goal of the Chapter III.

Summary

• Apart from VII, half-diminished chords rooted in II, III, and ♯IV are commonly used.
• The ♯IVø7 chord is distinctive for its standard bass movement of descending or ascending by a half-step, a characteristic feature.
• Occasionally, it makes sense to perceive ♯IVø7 as a rootless II9, and this is referred to as “rootless voicing”.

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