C Dominant seventh suspended fourth flat ninth flat thirteenth

The dominant 7sus4 with ♭9 and ♭13 is a hybrid sonority: the suspended fourth still gives the chord its wide, unresolved openness, while ♭9 and ♭13 import serious altered-dominant darkness from the jazz vocabulary. It is less “pure sus funk” and more cinematic: floating on top, heavy underneath. Use it when you want dominant time to feel stretched, ambiguous, and emotionally weighted.

Construction

Think in layers: 1-4-5-♭7 as the sus dominant frame, then add ♭9 and ♭13 as color tones (the fifth is often omitted first to reduce clutter). Spelling depends on register and instrument, but the ear should always catch the sus quality and the lowered extensions.

Usage

Common in modern jazz, fusion, and dramatic scoring on dominant pedals and in turnaround substitutions where a plain 7sus4 would sound too bright. It also works as a passing color between clearer dominants.

Examples

• Fusion progressions that alternate sus openness with altered shadows
• Film cues: dominant pedal with creeping chromatic upper lines
• Jazz arranging: reharmonized dominant stations with sus + altered extensions

Play

Keep the fourth and seventh readable, then place ♭9/♭13 away from the sus tone cluster if possible. If the voicing fights you, omit the fifth or distribute the root to bass.

Ear-training cues

You should hear both sus openness and altered ninth/thirteenth color—not only one of them.