The major seventh ♭5 chord pairs a major third and major seventh with a lowered fifth. That lowered fifth introduces a strong tritone-like interior interval against the third, so the chord sounds far less “plain major” than maj7 and more angular and modern. It appears in contemporary jazz, fusion, and reharmonized pop as a passing color or as an altered upper structure on static harmony.
Construction
Practical formula: 1-3-♭5-7. In Cmaj7♭5, a common spelling is C-E-G♭-B. Voice leading matters: the ♭5 wants to resolve melodically, often by semitone, while the major seventh still gives a “major family” brightness at the top.
Usage
Use it when you want major-seventh openness without the stability of a perfect fifth—especially in short moments between clearer chords, on pedal points, or as a reharmonization substitute for more common maj7 voicings.
Examples
- Modern jazz lines that treat ♭5 as a chromatic neighbor within major tonal centers
- Fusion progressions with shifting upper structures over a held bass
- Film and game scoring for chords that feel bright but unstable
Play
Keep 3 and 7 readable, separate ♭5 from the third in register when possible, and avoid doubling ♭5 in cramped voicings. If the chord sounds too sharp, widen spacing before removing the seventh.
Harmonic function in progressions
It is usually non-functional color rather than a classical diatonic goal chord: listeners feel major quality, but the lowered fifth prevents a fully “settled” triadic impression.
Ear-training cues
Hear major seventh at the top with an altered fifth interior—bright frame, uneasy middle.