Chord Rhythm
When you create a pattern, you specify the chord changes against which the pattern is most appropriately played. If any chords in the Chord Track would violate the chord rhythm of the pattern, the pattern is less likely to be selected for playback.
Specifying a chord rhythm does not dictate that chord changes must take place according to that rhythm while the pattern is playing. Rather, it stipulates that the pattern is best played in circumstances where chord changes do not fall outside the rhythm.
For example, you might set a chord rhythm for parts in a pattern containing linear statements that need to play though one whole measure without the chord changing beneath them. You mark only the first beat of each measure in the pattern as a valid point for a chord change. The pattern will not play in a section of a segment where the chords change more often than once per measure, unless no other suitable pattern is available.
On the other hand, many accompaniment parts consist of short statements that are not adversely affected when chord changes occur frequently. For example, a piano part that plays an arpeggio on each beat can sound fine if a different chord occurs on each beat. By marking all beats in this pattern as valid for chords, you ensure that the pattern can be selected regardless of the frequency of chords in the chord track.
To set a chord rhythm for a pattern, click the Set button in the Pattern Properties window. The Set Pattern Chord Rhythm Dialog Box appears.