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Many of you may already know about the traditional modes, and that they are based on the notes of the major scale:

The basic concept, as I see it, is that although the notes remain the same, the tonal center changes with the declaration of each different mode, with each different mode beginning on the next degree of the major scale. But there is one other major issue to consider when changing tonal centers—the intervallic relationship of each scale degree to the tonic changes with each different mode. This is why, in example one, I included not only the intervallic relationship between each note to the previous one as it ascends up the scale, but also the intervallic relationship of each note to its tonal center. And the tonal center is key (pun intended), because otherwise you run the risk of thinking you’re using a mode when you are in fact just using the different degrees of one scale.

Let’s frame it this way: it’s probably better to think about notes in the mode you’re using in terms of their intervallic relationship to the key you’re in than the scale degree you begin upon. To underscore this idea, a good exercise might be to write out the different modes using the same tonal center for each mode, and then identify each interval relative to the root tone:

You guys can do the rest, and then try this exercise with different starting notes as the exercise becomes more comfortable.

Now practice these different modes (with the same root) and begin to use them to improvise (or write something out) over a pedal tone (the root tone of the key you’re in as a sustained note accompaniment, as is common in East Indian music). Here is where you can really begin to hear how the color of the music changes with use of different modes over the same pedal tone. Notice that the only difference between the G Mixolydian scale and the G Dorian scale is the B flat, or minor 3rd, but that makes a huge difference in the sound of the scale against the tonic (as well as the chords that would be derived from this scale change, which I will discuss in my next article). Now, take note that the only difference between the G major (or Ionian) and the G Lydian scale is the C sharp, or augmented 4th. But this makes the difference between the opening line of The Simpsons sounding good or not:

Listen to audio of the "good" version.

Listen to audio of the "yuck" version.

I will continue discussing modes and their practical applications in next week's article. In the mean time, have fun exploring the modal possibilities we’ve looked at so far!

Composer, guitarist and arranger Steve Kirk's music has been featured in film, video games and TV. This includes music for the Disney game version of "The Princess And The Frog", Microsoft Games "Voodoo Vince" , the FarmVille Theme for Zynga Games, and to be released in Spring 2011, Cantina music composed for the Star Wars MMOL game The Other Republic.