Locrian natural 2 bb7 Mode on Guitar: Notes, Chords & Examples

  • May 21, 2026

Locrian natural 2 bb7 is a dark, tense, and highly unstable guitar mode built around a fully diminished sound.

Think of it as Locrian with two important twists:

  • The b2 becomes a natural 2, making it slightly more open and less claustrophobic.
  • The b7 becomes a bb7, giving the mode a strong diminished-chord identity.

The result is eerie, angular, and dramatic. It works especially well for progressive metal riffs, fusion lines, cinematic tension, and strange modal vamps where you want the tonic chord to feel unstable rather than resolved.

This is not a “happy” or “home base” mode in the usual major/minor sense. Its home chord is diminished, so it naturally wants to move, twist, or collapse into something else.

Formula

The interval formula for C Locrian natural 2 bb7 is:

1 2 b3 4 b5 b6 bb7

In interval names:

P1 M2 m3 P4 d5 m6 d7

Compared to regular Locrian:

  • Locrian: 1 b2 b3 4 b5 b6 b7
  • Locrian natural 2 bb7: 1 2 b3 4 b5 b6 bb7

That natural 2 gives the scale a slightly more melodic quality, while the bb7 makes the tonic chord fully diminished.

Notes in C

The notes of C Locrian natural 2 bb7 are:

C D Eb F Gb Ab Bbb

On guitar, Bbb sounds the same as A, but theoretically it is spelled B double-flat because it functions as a diminished seventh above C.

So in practical fretboard terms, you will often think:

C D Eb F Gb Ab A

But for theory accuracy, the correct spelling is:

C D Eb F Gb Ab Bbb

That final note is the one that creates the fully diminished sound.

The Chord That Defines the Mode

The defining chord of C Locrian natural 2 bb7 is:

Cdim7

Spelled:

C Eb Gb Bbb

This chord contains the most important color tones of the mode:

  • C = root
  • Eb = minor 3rd
  • Gb = diminished 5th
  • Bbb = diminished 7th

That gives you the classic fully diminished seventh chord.

A more colorful version is:

Cdim7(add9)

Notes:

C Eb Gb Bbb D

The added D, the natural 2, is what separates this mode from darker diminished or altered sounds. It adds a sharp melodic edge without removing the instability.

If you want to instantly hear the mode, loop a Cdim7 or Cdim7(add9) chord and improvise using the scale.

Chord Progressions

Because this mode has a diminished tonic, chord progressions should be treated more like modal vamps or dark harmonic environments than traditional major/minor progressions.

Progression 1

Roman numerals:

i°7(add9) – bVI – i°7

Chords in C:

Cdim7(add9) – Ab – Cdim7

This progression has a dark, ritualistic sound.

The Ab major chord gives the ear a moment of stability because it contains:

Ab C Eb

But returning to Cdim7 immediately pulls the harmony back into tension.

This works well for:

  • Slow doom/prog riffs
  • Cinematic clean guitar sections
  • Dark fusion vamps

Progression 2

Roman numerals:

i°7 – ivm – ii° – i°7

Chords in C:

Cdim7 – Fm – Ddim – Cdim7

This one feels more dramatic and gothic.

The Fm chord gives a minor-key flavor, while Ddim keeps the harmony tense and unstable. It is useful if you want a progression that moves but never fully relaxes.

Try palm-muting the roots and using upper-string chord stabs.

Example riff idea:

  • C pedal tone
  • Hit Cdim7 fragments
  • Move to Fm
  • Slide into Ddim
  • Return to Cdim7

Progression 3

Roman numerals:

i°7 – ivm/1 – bVI/1 – i°7(add9)

Chords in C:

Cdim7 – Fm/C – Ab/C – Cdim7(add9)

This is a great progression for progressive rock and metal because the bass can stay on C while the upper harmony changes.

The constant C pedal makes the mode feel centered, even though the chords above it are tense.

Mood:

  • Suspended
  • Mysterious
  • Cinematic
  • Slightly “wrong” in a good way

This is a strong choice for intros, breakdowns, or odd-meter clean sections.

Famous Songs and Guitarists Using C Locrian Natural 2 bb7

C Locrian natural 2 bb7 is an obscure synthetic mode, and there are no widely known guitar songs that are strongly and clearly associated with this exact mode.

That does not mean the sound is useless. It simply means you are more likely to hear its ingredients than the complete mode used as a strict scale.

Similar diminished and Locrian-like colors are commonly associated with:

  • Yngwie Malmsteen — diminished arpeggios and neoclassical tension
  • Ritchie Blackmore — dramatic diminished and harmonic minor-inspired guitar lines
  • Marty Friedman — exotic minor sounds and unusual interval choices
  • Allan Holdsworth — advanced altered and symmetrical harmony
  • King Crimson — dark, angular progressive rock harmony
  • Dream Theater-style prog metal — diminished riffs, unstable vamps, and modal tension

To be clear: these artists are not necessarily using C Locrian natural 2 bb7 specifically. But if you enjoy those darker diminished sounds, this mode gives you a fresh and highly focused version of that atmosphere.

Guitar Fretboard Shape

Here is a practical C Locrian natural 2 bb7 shape starting from C on the 8th fret of the low E string.

Remember: Bbb sounds like A on the guitar.

e|----------------------------11-13-14-16-17-|
B|-------------------10-13-15----------------|
G|-------------10-11-13----------------------|
D|-------10-12-13----------------------------|
A|-8-9-11-12---------------------------------|
E|-8-10-11-----------------------------------|

Notes:

C D Eb F Gb Ab Bbb

The most important tones to target are:

  • C — root
  • Eb — minor 3rd
  • Gb — diminished 5th
  • Bbb/A — diminished 7th
  • D — natural 2 color tone

Do not just run the pattern up and down. The mode sounds best when you emphasize the diminished chord tones and use the natural 2 as a melodic color.

Why Guitarists Love This Mode

Emotional Flavor

C Locrian natural 2 bb7 sounds tense, dark, and unstable.

It has the danger of Locrian, but the natural 2 gives it a slightly more open melodic quality. The bb7 pushes it toward a fully diminished sound, which makes it feel dramatic and unresolved.

It is excellent when you want something darker than minor but more specific than random chromatic notes.

Riff Potential

This mode is great for riffs because it contains several aggressive intervals:

  • b3 for minor darkness
  • b5 for tritone tension
  • b6 for heaviness
  • bb7 for diminished pull
  • natural 2 for a sharp melodic twist

Try building riffs around:

C - Eb - Gb - Bbb

That gives you the Cdim7 sound immediately.

Then add the D:

C - D - Eb - Gb - Bbb

That one extra note makes the riff sound less predictable.

Soloing Applications

This mode works well over:

  • Cdim7
  • Cdim7(add9)
  • Dark C pedal-point vamps
  • Diminished fusion sections
  • Progressive metal riffs using C, Eb, Gb, and A/Bbb

For soloing, start with the C diminished arpeggio:

C Eb Gb Bbb

Then add:

  • D for the natural 2 sound
  • F for a suspended color
  • Ab for extra darkness

This gives you melodic control instead of sounding like you are just running a strange scale.

Genres Where It Works Well

C Locrian natural 2 bb7 fits especially well in:

  • Progressive metal
  • Fusion
  • Dark jazz-rock
  • Cinematic rock
  • Experimental metal
  • Neoclassical shred
  • Horror soundtrack-style writing
  • Math rock or angular prog sections

It is not a common pop or blues mode, but for adventurous guitarists, it is a powerful color.

Tips for Practicing

Use a C Drone

Start with a low C drone.

You can use:

  • Open C drone from a looper
  • Synth pad
  • Bass note in your DAW
  • Low C power-chord-style pedal tone

Then slowly play the mode:

C D Eb F Gb Ab Bbb C

Listen carefully to how each note feels against the C.

Pay special attention to:

  • D — bright tension
  • Gb — unstable tritone
  • Bbb/A — diminished seventh pull

Try Simple Chord Vamps

Good practice vamps include:

Cdim7 - Cdim7(add9)
Cdim7 - Ab
Cdim7 - Fm/C - Ab/C

Keep the harmony simple. This mode already has a lot of tension, so you do not need complicated progressions to make it sound interesting.

Improvise with Small Motifs

Avoid scale-running at first.

Instead, create short phrases like:

C - D - Eb - Gb
C - Eb - Gb - Bbb
D - Eb - Gb - Ab - Gb

Repeat them rhythmically and move them around the neck.

This mode sounds especially good with:

  • Slides
  • Hammer-ons
  • Pull-offs
  • Wide vibrato
  • Tremolo picking
  • Odd rhythmic groupings

Target the Important Intervals

When improvising, aim for the defining tones:

  • b3: Eb
  • b5: Gb
  • bb7: Bbb/A
  • natural 2: D

The diminished chord tones create the identity.

The natural 2 creates the special modal color.

If your lines sound too random, return to the Cdim7 arpeggio and rebuild from there.

Try This Mode in SLModes

Want to explore C Locrian natural 2 bb7 more deeply?

Try it in SLModes.

SLModes helps you hear, visualize, and experiment with modes using:

  • Interactive chord options
  • Guitar fretboard layouts
  • Modal modulation tools
  • Scale and harmony exploration
  • Negative harmony experiments

For a mode this unusual, seeing the chords and fretboard together makes a huge difference.

Load up C Locrian natural 2 bb7, loop a Cdim7(add9) vamp, and start exploring its dark, diminished sound across the neck.