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:
A 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.)