和声走向：为什么和弦的顺序很重要？

Hi. This is Hub Guitar.

We're going to do a quick lesson about harmonic stress. Harmonic stress is the idea that, if you play a group of chords, the order matters. Each chord's relative weight or importance will be affected by the position it takes in the series.

Let's consider a C, Am, D, and G. These chords have the function of I, vi, ii, V.

In a series of four, the harmonic stress can be described as very strong, somewhat weak, somewhat strong, very weak. So the first chord is the heaviest, followed by 3. 2 is lighter, and 4 is the lightest.

So if we take these same four chords and change them around, the strength of each chord will increase or decrease based on its new position in the series. So I'm going to show you an example. Here is I, vi, ii, V.

This concept is often used as a guide when writing chord progressions. For instance a powerful-sounding chord will often be weakened by placement on a weak beat. That evens things out and prevents the chord from overpowering everything else.

So far, each of these chords took up one measure each consisting of four beats. But you can actually find another, deeper harmonic stress by dividing those measures into four beats. For instance, if we take the last measure, which is already the weakest measure, we'll find that the first beat in the last measure is the strongest in that measure, and the last beat in that measure is the weakest. So sometimes a very powerful and dissonant chord would be placed near the last beat of the last measure in a group of four. And that chord will sound very weak.