The diminished scale is an 8-note scale that is built by alternating whole and half steps from any root note.
There are two diminished scales in modern music, the fully diminished and dominant diminished scales.
Though they share a name, each scale is used to outline different chords in your solos.
The dominant scale is used to solo over 7th chords, and the other is used to solo over dim7 chords.
As well, each scale uses a different combination of whole and half steps.
Fully diminished alternates whole and half steps, while dominant diminished alternates half and whole steps.
Each scale brings a unique sound to dim7 and 7th chords in your solos.
And both are essential learning for any improvising guitarist.
In this lesson, you study diminished scale construction, apply these scales to dim7 and 7b9 chords, and learn diminished licks over progressions and songs.
Diminished Scale Contents
Whole Half Diminished Scale – Dim7 Chords
The first octatonic scale (8-note scale) is the whole half diminished scale, used to solo over Dim7 chords.
The whole half scale is used less often than half whole, mostly because dominant chords appear more frequently than diminished chords.
Called the “fully diminished scale,” whole half diminished alternates whole and half steps from any root note.
Hence the name.
This scale is used to solo over Dim7 chords, and DimMaj7 chords if you have the occasion to see that chord in a song.
When alternating whole and half steps, you produce the interval pattern for fully diminished.
R 2 b3 4 b5 #5 6 7
Or, from the root G the notes are.
G A Bb C Db D# E F#
As you can see, this scale has 8 notes.
Because of this, you sometimes mix #’s and b’s when writing it out.
As well, you have to use a letter name twice, which you wouldn’t with modes, as they contain 7 notes, one per letter name in the musical alphabet.
Fully Diminished – One Octave
Now that you know how to build fully diminished scales, you can take this scale to the fretboard.
Here are 12, one-octave fully diminished shapes to learn in the given key of C.
When ready, take this scale to every key in your guitar practice routine.
Learning one-octave fully diminished shapes allows you to apply this scale to fast chord progressions.
When chords move by at a fast tempo, or more than one chord per bar, large scales are too bulky to use in your solos.
When that happens, one-octave scale shapes come to the rescue.
Here are four fully diminished shapes beginning with your index finger.
Learn each shape from memory, then put on the jam track and solo with these scales in your guitar soloing practice routine.
Cdim7 Backing Track cdim7 backing track
Here are four fully diminished shapes starting with your middle finger on the first note.
The only exception is the last shape, which starts on your index finger.
Lastly, here are four fully diminished shapes that begin with your pinky finger.
Once you’ve checked out these fingerings, don’t worry if you can’t play them all from memory.
Pick a few to focus on and use them in your solos.
Over time, add more fingerings as you expand your knowledge of fully diminished on the fretboard.
When studying these fingerings, don’t only run them with a metronome in your practicing.
Use fully diminished in your solos is an important tool when mastering this scale on guitar.
So, after learning any fingering, put on the jam track and use that fingering over the Cdim7 chord.
Then, take that scale to chord progressions and full songs in your studies.
Fully Diminished – Two Octave
You now learn two-octave fully diminished shapes.
These larger shapes are useful when soloing over slower tunes and progressions.
As always, learn these fully diminished shapes from memory first.
Then jam over the Cdim7 backing track as you work this scale from a soloing perspective in your routine.
Cdim7 Backing Track cdim7 backing track
Once you have these shapes under your fingers, mix them with one-octave shapes to get the full picture of how to play this scale across the fretboard.
Fully Diminished Licks
One of the best ways to learn a new scale is to study essential jazz vocabulary for that scale.
Here are three fully diminished licks that you can apply to your guitar solos.
The first lick is played over a two-bar Gdim7 chord.
Click to hear whole half diminished scales 1
Next, you apply Bb fully diminished to the bIIIdim7 chord in a turnaround chord progression.
Click to hear whole half diminished scales 2
Lastly, here’s G# fully diminished applied to the #Idim7 chord in a turnaround.
Click to hear whole half diminished scales 3
Half Whole Diminished Scale – 7b9 Chords
The more popular of the two scales, half whole diminished is used over dominant chords when you want to bring a 13b9 sound to your solos.
As dominant chords are common in popular music, such as jazz, rock, and fusion, you see this scale pop up more often than fully diminished.
Because it’s used to solo over dominant chords, this scale is called the “dominant diminished scale.”
As the name suggests, dominant diminished is built by alternating half and whole steps from any root.
When doing so, you build the following interval pattern.
R b2 b3 3 #4 5 6 b7
Or, from a C root the notes are.
C Db Eb E F# G A Bb
Notice that you create tension when using dominant diminished over 7th chords.
As you progress with this scale, the biggest challenge is resolving that tension.
Make sure this is a priority, as it’s the difference between success and failure when using this scale in your solos.
As was the case with fully diminished, you sometimes mix sharps and flats when writing this scale, and have to use a note name twice.
Though they share a name, each diminished scale has a unique sound all it’s own.
To get your ears used to these sounds, play both back to back to hear how they compare on the fretboard.
Dominant Diminished – One Octave
Now that you know how to build dominant diminished, you can work this scale on the fretboard.
To begin, here are one-octave scale shapes to learn in the given key, C,
Then when you feel confident, move on to all 12 keys in your practice routine.
As was the case with fully diminished, these small shapes are ideal when soloing over fast chord progressions.
To get started, here are four dominant diminished shapes beginning with your index finger.
Once you can play any of these shapes, jam with them over the C7 track to hear how this scale sounds in a lead guitar situation.
C7 Backing Track C7 Backing Track
Here are four dominant diminished shapes starting with your middle finger.
The exception to this fingering guideline is the last shape, which starts on your index finger.
Lastly, here are four dominant diminished shapes that begin with your pinky finger.
Don’t forget to memorize these one-octave shapes and solo with them over the backing track in your studies.
Once you have any of these fingerings, take it further in your studies by holding down a C7 chord and singing the notes of C dominant diminished.
Singing is an effective way to build your ears with any new sound, especially one as tense as dominant diminished.
Even if you’re a terrible singer, I sure am, give it a try.
Just lock your door, close your windows, and turn on a fan.
No one will hear, and you get your ears to the next level in their development in no time.
Dominant Diminished – Two Octave
You now learn two-octave dominant diminished shapes on the fretboard.
When working larger scales, take a look at your fingers on each string.
Dominant diminished fingerings are symmetrical, just like the scale itself.
You can use fingers 1-2-4-4 on every string going up the scale.
Then, on the way down use 4-3-1-1.
This allows you to use one fingering on each string up and then down the scale.
Making it easy to memorize and apply across the fretboard.
C7 Backing Track C7 Backing Track
Once you have these two-octave shapes under your fingers, bring them together with the one-octave shapes you learned earlier.
Mixing scales of different lengths is a great way to push yourself in new creative directions in your solos.
You might find that you prefer certain phrases with shorter scales, and different ones with longer scales.
Give this mixture exercise a try and see where it leads you in your practice routine.
Dominant Diminished – Licks
In this final section of the lesson, you learn three dominant diminished licks over popular chord progressions.
When learning these lines, don’t just focus on the tension created by this scale over each 7th chord.
Instead, notice how this tension is resolved in the progression.
To paraphrase Stevie Ray Vaughan:
“It’s real easy to go outside, but it’s much harder to get back inside.”
If you use dominant diminished in your solos and don’t resolve the tension, you’re gonna have a bad time.
But, if you can resolve that tension properly, you bring new levels of energy to your solos.
There’s a fine line between a mistake and a cool lick.
Finding that line is your goal with any tension creating scale such as dominant diminished.
This first line is played over a G7 chord, and the tension is resolved to the root at the end of the phrase.
Click to hear half whole diminished scale 1
Next, you apply G dominant diminished to the the V7 in a ii-V-I chord progression.
Click to hear half whole diminished scale 2
Lastly, here are the G and C dominant diminished scales applied to the first four bars of a 12-bar blues progression.
Click to hear half whole diminished scale 3
Jazz Blues Diminished Solo
Here’s a solo over a G blues progression that uses diminished sounds over just about every chord.
Learn each phrase one at a time, then bring them together to play the solo as a whole.
There’s also a backing track to use as you bring these scales into your own improvised jazz solos.
Backing Track g-dim-blues-backing
Click to Hear diminished-scale-solo