Zitat
The song's key is Db Major. That means that the root chord is a Db major chord. Usually, a Ab major chord will lead into a Db major. This is the V-I chord progression and it is known as the Authentic Cadence. Now, it seems to resolve to a sadder chord at the end of the phrase. Instead of ending on Db major, it lands on Bb minor: the relative minor of Db major. When a chord progression seems to be heading to the root chord but lands on the relative minor, that is called...
...Deceptive Cadence
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