Apple Logic Pro 9 - Manual (Page 176)

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Click the Sample Rate display in the Transport bar, then choose a sample rate from the
pop-up menu.
Note: If your Transport bar does not include the Sample Rate display, Control-click it and
choose Customize Transport Bar from the shortcut menu. Select the Sample Rate or Punch
Locators checkbox in the Customize Transport Bar dialog.
You may find that audio files in your project do not match the newly selected sample
rate. The playback of files that do not match the project’s sample rate is slower (file’s
sample rate is higher) or faster (file’s sample rate is lower) than it should be.
To match a file’s sample rate with the project sample rate
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Use the Audio Bin’s Copy/Convert File(s) command (which is also available by
Control-clicking the Audio Bin 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 does not 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 does not 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 a notebook computer, or setup that does not support the original
project’s sample rate, will commonly 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: High sample rates not only use up disk drive space, but also result in a higher
processing load.
Setting the Project Tempo
You can set the basic project tempo in the Transport bar, the Tempo track, or the Tempo
List. Logic Pro displays tempo as quarter notes per minute, or beats per minute (bpm). It
ranges from 5 to 990 bpm, and is adjustable to four decimal places after the whole value.
176 Chapter 7 Working with Projects