C# Half-Whole Diminished Scale

What is the C# Half-Whole Diminished Scale?

The half-whole diminished scale reverses the diminished pattern, starting with a half step then a whole step. This version is the classic choice for soloing over dominant 7th chords in jazz — it packs in ♭9, #9, #11, and natural 13 tensions, giving you a dense palette of colorful alterations over a single chord. Here's how the C# Half-Whole Diminished Scale lays out on the fretboard. This scale is enharmonically equivalent to Db Half-Whole Diminished.

Notes and Positions

Dominant-use symmetric scale starting with a half step. On bass, the fretboard view helps you visualize where the important tones sit for building lines across positions. Use a finger-per-fret approach first, then add shifts only when the line needs a wider range. In the key of C#, the notes are: C#, D, D##, E#, F##, G#, A#, B.

How to Use It

You'll often hear it in Jazz, Fusion, and Dominant V chords. A good way to internalize the sound is to sing the root, then sing a few scale degrees before you play them.

Practice root-on-E and root-on-A boxes separately, then connect them with one clean position shift. Use the interactive fretboard above to spot repeats of the same note on different strings and frets.