What is the C# Altered Scale?
The altered scale (also called Super Locrian) is the seventh mode of the melodic minor scale, and it lives up to its name — every possible tension is altered (♭9, #9, ♭5/#11, #5/♭13). It's the ultimate dominant tension scale in jazz, used over V7 chords when you want maximum harmonic tension before resolving. Here's how the C# Altered Scale lays out on the fretboard. This scale is enharmonically equivalent to Db Altered.
Notes and Positions
All altered tensions over V7; 7th mode of melodic minor. On guitar, you can treat this as both a lead vocabulary and a way to see chord tones inside common shapes. Start with one box, then connect it to the nearest root on the next string set. In the key of C#, the notes are: C#, D, D##, E#, F##, A, B.
How to Use It
You'll often hear it in Jazz, Fusion, and Altered dominant chords. A good way to internalize the sound is to sing the root, then sing a few scale degrees before you play them.
Practice in small fragments (3-4 notes) and connect them across adjacent positions. Use the interactive fretboard above to spot repeats of the same note on different strings and frets.