The Shell and More

When it comes to extended harmonies, the most important tones are the third, seventh and ninth. So, in the key of C (major, dominant and minor), these are:

Of course, this doesn’t make much sense in the ear until the bass is added:

Bottom line, however: if, when accompanying a soloist or playing in a rhythm section, you did nothing more than play the third, seventh and ninth of an extended chord, you’d be just fine.  By the way, this handy little triad is what my professors referred to as the “Shell” – as in the harmonic “shell” that is placed over the root tone.

Now, let’s move on to 11th chords. In major tonality, the 11th chord has a “Lydian” quality. In case you’ve forgotten your modes (or never learned), the Lydian mode is a major scale with a raised fourth, like so:

Here’s the major 11th chord. Here’s the major 11th chord. Can you hear the relationship?

If you want to get the real flavor of an 11th chord without having to play all the notes (I’m addressing guitar players, here), you could play the minor triad corresponding to the key one-half step below the current harmonic structure. In C major, this would be a B minor triad an octave higher:

To give it a “dominant” or “blues” flavor with a flatted seventh, go down another half-step and build an augmented triad:

minor 11th chord can be created with the use of a major triad based on the flatted seventh and played an octave higher:

Next time, we’ll examine the 13th chord.  Until then, thanks for viewing! (By the way, if you are a musician who is genuinely interested in this topic, feel free to leave a comment and a link to your music-related blog. I’ll be happy to take a look and even provide a return link.  If, on the other hand, you are trying to sell insurance, “get rich quick” schemes, viagra or something else that has nothing to do with thie topic of this blog, please don’t waste your time and mine.)


Print Friendly

About KJ at Guide Tone Lines

KJ McElrath earned his Masters degree in Music Theory and Composition from Central Washington University. Composer of several works for big band, wind ensemble and orchestra, which can be heard at I perform a cabaret act with Athena McElrath as McElrath Cabaret, which you can find at
This entry was posted in changes, chord extensions, chord progression, color tones, guide tone lines, guitar shortcuts, harmonic structures, modal scales, modes, music theory, truncated chords, truncated harmonies and tagged , , , , , , , , , , , , , , , , , . Bookmark the permalink.

One Response to The Shell and More

  1. Pingback: Lucky Thirteenth | Guide Tone Lines