Related ii chord: a ii(7) chord that occurs before a secondary dominant and is in the key being tonicized. The inclusion of this chord creates a (ii-V)/x progression.
In the past lesson, we have seen examples of related ii chords in ii7-V7 progressions.
Related ii chords can also progress to a tritone substitution (a ii7-TTsub progression).
Let’s look at the example below. Listen and analyze the chords.
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An analysis of this example is shown below. The chord in m. 2, the Eb7 chord, is a tritone substitution for the dominant V7 of the D-7 chord – an A7 chord. It is analyzed as a TTsub/ii.
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In the example below, the tritone substitution is preceded by a Bb-7 chord.
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If the Eb7 were a V7 chord in a key, we would be in Ab. The Bb-7 chord would then be the ii7 chord in the key of Ab. The Bb-7 and Eb7 chords would be analyzed as a ii7-V7 progression in the key of Ab.
However, the Eb7 chord is the TT sub in the key of D minor. To show the TT sub, we have analyzed the progression as shown below..
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Summary
We have seen in the above lessons many examples of related ii chords.
Related ii chord: a ii(7) chord that occurs before a secondary dominant and is in the key being tonicized. The inclusion of this chord creates a (ii-V)/x progression.
Related ii chords can also come before tritone subs as seen above.
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