Set the project sample rate
The project’s sample rate determines the number of samples Logic Pro uses for audio playback. When you record or add audio files to your project, their sample rate is matched to the project sample rate if the “Convert audio file sample rate when importing” project setting is active. You can turn on this setting in the File > Projects Settings > Assets pane.
Some audio files in your project may not match the newly selected sample rate. The playback of files that don’t match the project’s sample rate is slower (the file’s sample rate is higher) or faster (the file’s sample rate is lower) than it should be. You can match the sample rate of individual audio files to the project sample rate in the Project Audio Browser.
Set the project sample rate
Do one of the following:
Choose File > Project Settings > Audio (or use the Open Audio Project Settings key command), then choose a sample rate from the Sample Rate pop-up menu.
Click the Sample Rate display in the LCD, then choose a sample rate from the pop-up menu.
Note: If the LCD does not show the Sample Rate display, Control-click the LCD and choose Customize Control Bar from the shortcut menu. Select the Sample Rate checkbox in the Customize Control Bar dialog.
Match a file’s sample rate with the project sample rate
Use the Project Audio Browser’s Copy/Convert File(s) command (which is also available by Control-clicking the Project Audio Browser or using the corresponding key command), then replace the file in the project.
Logic Pro performs a real-time, native sample rate conversion. Any sample rate available in Logic Pro (via Audio > Sample Rate) can be used for the conversion—even if your audio hardware doesn’t support the selected sample rate.
The native software sample rate conversion function matches the sample rate of any audio hardware, thereby allowing the playback of projects on virtually any audio system, even if the hardware is—in sample rate terms—not compatible. Nothing is lost in the process. Any internal processing and bouncing is always performed at the original sample rate, and at the highest quality, even in cases where the hardware doesn’t support a particular sample rate. This feature allows you to work on projects originally created on high-end audio systems, with lower-end setups.
For example, imagine a project was created with audio hardware set to operate at 96 kHz. Moving this project to another computer (for example, a notebook computer) that doesn’t support the original project’s sample rate will result in the wrong playback speed. The native real-time sample rate conversion function will counteract this effect, allowing correct playback of the project on the portable computer, at any sample rate.
Note: Higher sample rates not only use up more disk space, but also require more processing.