Altered

Dominant seventh, sharp nine chords

Dominant 7 with #9: C-E-G-Bb-D#. Formula: 1-3-5-b7-#9. The 'Hendrix chord' — bluesy and raucous.

In every key

The same shape, moved. The symbols below are spelled the way the app spells them, which is the spelling the chord's own scale asks for rather than whichever accidental is easier to type.

  • C7#9
  • Db7#9
  • D7#9
  • Eb7#9
  • E7#9
  • F7#9
  • F#7#9
  • G7#9
  • Ab7#9
  • A7#9
  • Bb7#9
  • B7#9

Voicings

Written in C, because that is the key the encyclopedia authors them in; every one transposes unchanged.

Rootless Type A (3-b7-#9-5)

E · Bb · D# · G

intermediate

Rootless Type B (b7-#9-3-13)

Bb · D# · E · A

advanced

Hendrix Voicing

C · E · Bb · D#

intermediate

Octaves shown are the app's default ascending voicing.

The iconic Purple Haze voicing — full chord from root

Full Altered Spread

E · G · Bb · D# · A

expert

Octaves shown are the app's default ascending voicing.

Upper Structure bIII (Eb) (#9-5-b7)

D# · G · Bb

intermediate

RH 1-2-4; keep the cluster compact, let the LH carry the 3rd (E) for the bite.

Where it turns up

Funky V7 sound. Hendrix Purple Haze. Common in modern jazz, blues, and fusion.

Commonly swapped with

  • C7
  • C7alt
  • C13#9