Ionian #2 #5 Mode on Guitar: Notes, Chords & Examples

  • May 21, 2026

Ionian ♯2 ♯5 is a bright but strange major-based mode with an augmented, almost cinematic edge. It sounds “major” because it has a natural 3rd and major 7th, but the raised 2nd and raised 5th make it feel unstable, exotic, and futuristic.

For guitarists, this mode sits somewhere between:

  • A dreamy major scale
  • An augmented fusion color
  • A progressive rock/metal synthetic scale
  • A film-score style “mystery major” sound

It is not a common everyday mode like Dorian or Mixolydian. It is an advanced synthetic mode, so its power comes from using the color notes carefully rather than just running the scale up and down.

In C, the mode is especially striking because it contains two tight chromatic clusters:

  • D# E F
  • G# A B C

Those half-step movements are perfect for eerie melodies, angular riffs, and modern fusion lines.

How does it sound?

Before anything else, let’s hear how it sounds. This can best be done by playing a chord from the mode, and playing the notes of the mode arpeggiated on top of it. This is the best and quickest way to determine the feel of a mode.

This can be quickly done using SLModes, a software dedicated to the music modes, and the following sound was generated by it:

Formula

The interval formula for Ionian ♯2 ♯5 is:

1 ♯2 3 4 ♯5 6 7

In interval names:

P1 A2 M3 P4 A5 M6 M7

Compared to the regular Ionian mode, also known as the major scale, Ionian ♯2 ♯5 raises the 2nd and the 5th:

C Ionian: C D E F G A B C Ionian ♯2 ♯5: C D# E F G# A B

The result is still major, but much more tense and colorful.

Notes in C

The notes of C Ionian ♯2 ♯5 are:

C D# E F G# A B

Because this is an altered major mode, spelling matters.

You may notice that D# sounds like Eb, and G# sounds like Ab. But theoretically, they are written as ♯2 and ♯5 because the mode is built from a major/Ionian framework with raised scale degrees.

So the correct scale-degree spelling is:

  • C = 1
  • D# = ♯2
  • E = 3
  • F = 4
  • G# = ♯5
  • A = 6
  • B = 7

The Chord That Defines the Mode

The defining chord of C Ionian ♯2 ♯5 is:

Cmaj7♯5(#9)

Notes:

C E G# B D#

This chord captures the sound of the mode beautifully because it includes the most important color tones:

  • C = root
  • E = major 3rd
  • G# = raised 5th / augmented color
  • B = major 7th
  • D# = raised 2nd, usually heard as #9 in chord form

A simpler version is:

Cmaj7♯5

Notes:

C E G# B

This already gives you the dreamy augmented-major sound. But adding the D# brings out the full personality of the mode.

On guitar, try this chord shape:

Cmaj7♯5(#9)

E|--11--
B|--12--
G|--13--
D|--10--
A|------
E|--8---

This is not a basic campfire chord. It is tense, colorful, and very useful for fusion, progressive rock, cinematic metal, and modern songwriting.

Chord Progression (Example)

Because C Ionian ♯2 ♯5 is an advanced synthetic mode, it works best with modal vamps and color-based progressions rather than traditional major-key harmony.

The goal is to keep C feeling like home while using chords that highlight the raised 2nd and raised 5th.

Roman numerals:

Imaj7♯5(#9) – IVmaj7 – Imaj7♯5

Chords in C:

Cmaj7♯5(#9) – Fmaj7 – Cmaj7♯5

This progression moves from the strange augmented tonic to a warmer IV chord.

Mood: Floating, cinematic, mysterious, but still emotionally “major.”

The Fmaj7 gives the ear a more familiar place to rest, while the return to Cmaj7♯5 brings back the unstable Ionian ♯2 ♯5 flavor.

Try soloing over this vamp and emphasizing:

  • D# resolving to E
  • G# resolving to A
  • B resolving to C

Guitar Fretboard Shape

Here’s the mode mapped across the full fretboard, generated with my software SLModes.

The diagram shows every occurrence of the mode across the neck:

🟢 Green dots = the root note, your anchor points
🟠 Orange dots = the rest of the scale tones

Why Guitarists Love This Mode

Emotional Flavor

C Ionian ♯2 ♯5 is bright, but not simple.

It has a major tonic, a major 7th, and a natural 6th, so it can sound beautiful and open. But the ♯2 and ♯5 add tension, mystery, and unease.

It is a great mode when regular major sounds too plain, but you still want something with a strong major identity.

Riff Potential

This mode has excellent riff potential because of its chromatic clusters.

Try building riffs around:

C D# E F

or:

G# A B C

These note groups work well for:

  • Progressive metal riffs
  • Odd-meter patterns
  • Tapped sequences
  • Dissonant pedal-tone ideas
  • Cinematic lead hooks

A simple riff idea:

E|----------------|
B|----------------|
G|----------------|
D|---------9-10---|
A|-8-11-12--------|
E|-8--------------|

That gives you:

C D# E B C

It immediately sounds more unusual than a standard major or minor riff.

Soloing Applications

C Ionian ♯2 ♯5 works especially well over:

  • Cmaj7♯5
  • Cmaj7♯5(#9)
  • Caug
  • Cmaj7 with altered upper extensions
  • Static C pedal tones
  • Fusion-style major vamps

When soloing, do not treat every note equally.

Strong target notes:

  • E = major 3rd
  • G# = ♯5
  • B = major 7th
  • D# = ♯2 / #9 color tone

Great resolutions:

  • D# to E
  • F to E
  • G# to A
  • B to C

Genres Where It Works Well

C Ionian ♯2 ♯5 can work in:

  • Progressive rock
  • Progressive metal
  • Fusion
  • Modern jazz guitar
  • Instrumental rock
  • Film/game music
  • Experimental songwriting
  • Ambient guitar music

It is especially useful when you want a sound that is major, but twisted.

Tips for Practicing

Use a C Drone

Put on a low C drone and play the scale slowly.

Do not rush.

Listen to each note against the drone:

  • C sounds stable.
  • D# sounds tense and exotic.
  • E confirms the major quality.
  • F adds suspension.
  • G# creates the augmented flavor.
  • A adds brightness.
  • B pulls strongly back to C.

This is one of the best ways to understand the mode emotionally.

Practice Chord Vamps

Try looping these vamps:

Cmaj7♯5(#9) - Fmaj7
Cmaj7♯5 - G#m
Cmaj7♯5 - Am(maj7)
Cmaj7♯5 - E - B7b5 - Cmaj7♯5

Keep the rhythm simple at first. Let your ear absorb the sound before making the harmony too busy.

Improvise with Small Motifs

Instead of running the full scale, create short phrases.

Try limiting yourself to:

C D# E F

Then try:

G# A B C

Then combine them.

This mode sounds strongest when you highlight its unusual intervals intentionally.

Target the Important Intervals

Focus your lines around the characteristic tones:

  • ♯2 / D#
  • ♯5 / G#
  • 7 / B

For example, over Cmaj7♯5, try resolving:

D# -> E
G# -> A
B -> C

These small movements make the mode sound expressive instead of random.

If you like modes, SLModes is for you

SLModes is the software for exploring everything related to music modes.

It helps you experiment with:

  • Modal chords
  • Guitar fretboard shapes
  • Chord progressions
  • Modal modulation
  • Negative harmony ideas

If you play guitar and want to access 60+ music modes, SLModes is waiting for you

Learn more about SLModes

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