Gb7#5 Piano Chord

Piano Diagram of Gb7#5 in Root Position

A Gb7#5 chord is an altered dominant seventh chord that is built upon the key of Gb. This chord consists of the root note Gb, the major third Bb, the augmented fifth D and the minor seventh Fb. However, due to the dissonance created by the augmented triad, the Gb7#5 chord can be used as a substitute for dominant chords only in specific musical contexts. Another common use of this chord is as part of a modulation to or from a Gb7 chord. If you keep reading, you will learn more about the music theory that underpins this chord.

 

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Structure of Gb7#5

 

Fingers Position

How to play a Gb7#5

To play a Gb7#5 chord, you can use the following voicing: begin by playing the root note Gb with your left hand. Then, with your right hand, play the notes Fb (natural E, minor 7th), Bb (major 3rd), and D (sharp 5th).

Gb + Fb, Bb, D

This will result in a voicing of Gb7#5 that includes all notes: the root note, major 3rd, minor 7th, and sharp 5th.

 

Gb7#5 Chord Inversions

 

The Gb7#5 chord has a total of 3 inversions:

 Piano Keyboard Diagrams

Chord Inversions on Piano

A solid grasp of chord inversions is essential in music theory as it provides insights into how chords are built. When playing chord inversions on a piano, it’s crucial to realize that the charts depicting the note order may not always be practical or playable.

To achieve the correct chord voicings on a piano, you need to distribute the chord notes across different octaves and positions on the keyboard. This often involves deviating from the standard shape of the chord’s inversions presented in charts, which may not be the most practical or comfortable way to play the chord.

While chord inversion charts are useful for understanding the structure and sequence of notes in a chord, it’s advisable to experiment with different voicings and fingerings to discover the most efficient and comfortable way to play the chord, while still maintaining its intended harmonic function and sound.

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Music Theory and Harmony of Gb7#5

 

Dominant 7#5 chords are often used as a transitional chord to add an extra layer of tension to a dominant 7th chord and prepare for the resolution to the tonic. The Gb7#5 chord can substitute or enhance the Gb7 chord, commonly on the V degree, but also on the III degree, and occasionally on other degrees as a secondary dominant chord.

Before examining the most common use of this chord, let’s learn how to build it.

 

Building the Gb7#5 Chord: Different Approaches

 

Starting from the Gb Major Scale:

To form a Gb7#5 chord, you combine the root (Gb), the major 3rd (Bb), the augmented 5th (D), and the minor 7th (Fb) from the Gb scale.

 

 

 

To create a Gb7#5 chord, apply the formula R, 3, #5, m7 in the following manner:

1. Begin with the Root note, Gb.
2. Select the major 3rd interval, which is Bb.
3. Add the 5th interval, which is Db then raise it by half step: D.
4. Add the minor 7th interval, Fb (E).

By following this simple formula, you can create a 7#5 chord from any major scale.

 

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by Combining Intervals:

One method to create a 7#5 chord is by combining specific intervals – a major 3rd, a major 3rd, and a 2nd.

3 + 3 + 2 = 7#5 Chords

For example, to build a Gb7#5 chord:

• we start with the root note Gb.
• We then add a major 3rd interval, which is four half-steps up from the root, to get Bb.
• Next, we add another major 3rd interval, which is again four half-steps up from Bb, to get D.
• Finally, we add a 2nd interval, which is two half-steps up from D, to get Fb (E).

Together, these intervals form the Gb7#5 chord.

 

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How to Use Gb7#5 in a Chord Progression

 

The Gb7#5 can work as a substitute or as a passing chord to a Gb7 that can be found in major and natural minor scales. However, note that it’s a non-diatonic chord due to the presence of the augmented 5th.

These tables show the harmonized major and natural minor scales where you can find a Gb7 or use it in place of other chords.

Most common uses of Gb7#5

Gb7#5 in Cb Major and Cb minor

The Gb7#5 chord is a popular choice for creating tension in music, often functioning as a dominant chord. In the context of the key of Cb major, you can use Gb7#5 as the V7 chord, setting the stage for a resolution back to the I chord (Cb major).

However, since Cb major is a theoretical key, we will refer to its enharmonic equivalent key B major.

• Substitute or Passing Chord to the Dominant chord in B Major as F#7#5

 

Gb7#5 as Substitute for Gb min7

The Gb7 chord, taken from the harmonic minor scale, could act as substitute for a Gb min7 chord in the key of Cb minor. In certain situations, you can also opt for the Gb7#5 chord instead of the Gb7 chord, intensifying the harmonic tension and guiding the progression towards the Cb min7 chord.

As before, we will refer to the enharmonic equivalent key of Cb minor, although it is a theoretical key and is seldom, if ever, used in practice.

• Substitute or Passing Chord to the Dominant chord in B minor as F#7#5

 

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Gb7#5 in a I – III7 Progression

The Gb7#5 chord could be used as a substitute for the III degree in a I – III7 chord progression. This progression typically involves a Gb minor chord, but when using the chords Ebb Maj7 (I) and Gb7 (III7), you can introduce the Gb7#5 chord instead of the usual Gb minor chord.

Again, we are in a theoretical key (Ebb) so we will refer to the equivalent key, D major.

• Substitute or Passing Chord to the Mediant chord in D Major as F#7#5

 

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Gb7#5 in Ab minor

Although the Gb7#5 chord can find a place in the key of Ab minor, it might not be as commonly used in this context.

• Substitute or Passing Chord to the Leading Tone chord in Ab minor (less common)

 

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Gb7#5 as Substitute for a Secondary Dominant 7th chord

A secondary dominant is a chord that doesn’t belong to the main key of a musical piece but is used to strongly lead to another chord that does. In Western music, the fifth note of the scale has a powerful “dominant” role, creating tension that naturally resolves to the first note of the scale (I). A secondary dominant chord serves the same purpose but directs this dominant function to a different chord, causing a temporary shift away from the main key.

For instance, in the theoretical key of Fb major, the Cb7 chord serves as the V chord, leading back to the I chord of Fb Maj7. Introducing an additional chord between Fb Maj7 and Cb7 that strongly gravitates towards Cb7 results in a secondary dominant chord. In this scenario, including a Gb7 chord generates a pull towards Cb7, as Gb7 functions as the V chord in the key of Cb.

| Fb Maj7 | Cb7 |

⇒

| Fb Maj7 | Gb7 | Cb7 |

Instead of using a standard Gb7 chord, you can opt for the Gb7#5 chord in its place or in combination with it. This substitution or addition can add more tension and complexity to the progression, leading to a more interesting and dynamic musical result.

| Fb Maj7 | Cb7 |

⇒

| Fb Maj7 | Gb7/Gb7#5 | Cb7 |

 

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Gb7#5 Chord Function in Major and Minor Keys

 

Gb7#5 as Dominant Chord in Cb Major

Check F#7#5 in B Major

 

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Gb7#5 as Dominant Chord in Cb minor

Check F#7#5 in B minor

 

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Gb7#5 as III7 Degree in Ebb Major

Check F#7#5 in D Major

 

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Gb7#5 as Leading Tone Chord in Ab minor

In the key of Ab minor, the Gb7 chord is constructed on the leading tone, which is the seventh note of the scale. This chord can be substituted or changed to a Gb7#5, although it might not be the most optimal position for this chord. Nevertheless, it remains a valid choice in specific musical situations.

 

Gb7#5 as VII degree – Chord Progressions

 

i iv VII i

 

i VII VI V

 

i III VII VI

 

i iv VII VI

 

i iv VII III

 

Circle Progression

 

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Alternative Gb7#5 Nomenclature

• Gb 7+5
• Gb 7(#5)
• Gb aug7
• Solb 7#5
• Gb 7#5th
• Gb 7 aug5
• Gb Dominant 7th #5
• Gb Dominant Seventh Sharp Fifth

 

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