Part 12: Blues, with the foundations still clear · Lesson 113 / 117
One C changes role as the blues chord changes
Explain the major/minor mixture without declaring the note simply wrong.
A7 contains A–C#–E–G. A melody C above it is a minor third relative to A, contrasting with the chord's major third C#. That expressive major/minor relationship is part of blues vocabulary.
D7 contains D–F#–A–C. The same C is now a chord tone: its minor seventh above D. Relative to the overall A tonic, C is still b3. The pitch did not change, but the chord reference did.
Hold or repeat a C while the backing changes from A7 to D7. Listen to the difference in its surroundings. Then play C–C# over A7 and C over D7 as two deliberately different choices.
A fret-based scale shows discrete pitches, while blues performance may bend or shade pitches between them. Our notation provides clear reference targets; real expressive inflection is not always confined to a single fixed fret pitch.
Hear it
Blues C Role
Audio fileFour-beat count-in · 60 BPM · Warm sampled electric guitar. Listen once before playing along.
A concrete example
C over A7: b3 above A, outside the chord's major triad. C over D7: b7 above D, a chord tone. Tonic-relative label remains b3 in both.
Try it, slowly
- Play C over A7 and identify the chord's C# separately.
- Keep C while D7 arrives.
- Explain both chord relationships and compare a C→C# resolution over A7.
Check one idea
Does C become a different scale degree above tonic A when D7 begins?
Show the explanation
No. It remains b3 relative to A. Its role relative to the current chord changes to the minor seventh above D.
A good place to stop
You can explain the blues mixture using two clear reference points.
Return to the example after a short break. A clear explanation matters more than speed.
