Here’s what to do if your project tempo doesn’t match your loop’s tempo
OBJECTIVE: Match a loop’s tempo to the project tempo, either by changing the tempo to match that of the loop, or changing the loop tempo to match that of the project.
BACKGROUND: There are many ways to “stretch” loops so that they’re compatible with project tempo, including the use of Apple Loops or REX files. But if a loop is a standard WAV or AIF file, you can still do stretching via Logic Pro 9’s DSP.
1. Import the loop into the Arrange view, then click on it to select it.
2. Ctrl-click on the Cycle button in the Transport bar, then de-select Auto Set Locators.
3. Set the locators to the target length for the loop. In this screen shot, the eight-bar loop is slower than the project tempo; note how the locators mark eight bars.
4. Decide if you want to match the project tempo to the loop, or the loop to the project tempo. If the former, go Options > Tempo > Adjust Tempo Using Region Length and Locators. If the latter, proceed to Step 6.
5. A dialog box asks if you want to create a tempo change, or change the project tempo globally. In this case, we want a global change to match the loop. After clicking on Globally, the tempo will change to match the loop. Done!
6. Go Audio > Time Stretching Algorithm, and choose an algorithm appropriate to the material being stretched.
7. To match the loop to the project tempo, again with locators set to the target number of bars and the loop selected, go Audio > Time Stretch Region to Locators. The tempo will remain the same, but the loop length will change to the number of bars set by the locators.
¦ In Step 7, if the audio quality of the loop is degraded on playback, go Edit > Undo Adjust Region Length. Return to Step 6, choose a different algorithm, and try again. Keep trying different stretch algorithms until you obtain the best possible stretching quality.
¦ In Step 7, you can also choose Audio > Time Stretch Region to Nearest Bar if the locators aren’t set as desired, and the nearest bar is close to the end of the region.