How to Build Dim7 Arpeggios

In today’s theory lesson, we’ll be building on the m7b5 Arpeggios that we previously looked at, and dig into building dim7 Arpeggios, or fully-diminished arpeggios as they are sometimes called.

There are two different ways that you can build these arpeggios, the first being related to the diminished triad. If you need a refresher on these triads, check out the How to Build Diminished Triads lesson for more info.

In the example below, you can see a Diminished Triad, C-Eb-G or 1-b3-b5 intervals, next to a Cdim7 Arpeggios, C-Eb-Gb-Bbb or the intervals 1-b3-b5-bb7.

The bb7, or diminished 7 interval, is a bit of a funny one. Bbb in this case is the same note as A on the fretboard, but written on the staff it looks different due to the fact that it is a 7th in the key and not the 6th, as A would be. More on these intervals in the What Are Diminished Intervals lesson.

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The second way that you can build a dim7 arpeggio is taking the 1st, 3rd, 5th and 7th notes from the Whole-Half Diminished scale.

You can see this technique below, where I took those notes from the C Whole-Half Diminished Scale and used them to build the Cdim7 Arpeggio in the bar next to it.

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