Change the musical length of a pattern in Logic Pro for Mac
Several factors determine the musical length of a Step Sequencer pattern (the time in bars and beats before the pattern repeats). The most fundamental are the pattern length, which defines the maximum number in steps available to each row, and the pattern step rate, which defines the length of each step in musical divisions (note values).
Another important factor affecting the musical length of a pattern is the Loop Start/End edit mode. Using Loop Start/End, you can set the number of steps for each row independently from the pattern length and the length of other rows. Technically, the musical length of a pattern is the length of the longest row. For example, if all rows in a pattern loop after four steps, and each step has a step rate of 1/16, then the musical length is only one beat (1/4), even if the pattern length is 16 steps or longer.
When row lengths are evenly divisible with one another, the overall length is equal to the longest row. For example, if you shorten several rows in a 16-step pattern to four or eight steps (which both divide evenly into 16), the pattern remains a one-bar pattern. When row lengths are not evenly divisible, however, the musical length is increased (sometimes substantially) because the pattern doesn’t repeat until all rows start at the same time again.
Using the Skip edit mode can also result in the length of rows changing, which affects the overall musical length of the pattern in a similar manner to changing the Loop Start/End setting.
The playback mode can also affect the musical length of the pattern. Choosing Ping-Pong as the playback mode doubles the pattern length, while setting any row to Random playback mode can result in the musical length of the pattern being essentially infinite.
Ultimately, how long a pattern plays in a project depends on the length of the pattern region or pattern cell. If the musical length of the pattern exceeds the region or cell length, it plays only until the end of the region or cell is reached. When the region or cell length exceeds the pattern length, the pattern repeats until the end of the region or cell, or restarts if the region or cell is looping. If the musical length of the pattern, or of any row, does not fit equally into the region length (or cell length), then the rows in the pattern restart before they complete a full cycle.
