Apple Logic Express 7 - Manual (Page 145)

Chapter 4 Audio in the Arrange Window 145
Stereo Recordings
For information on creating stereo recordings, please read the appropriate Mixers,
Effects, and Audio Objects sections; Stereo Objects (see “Stereo Objects” on page 203)
and Channel Strips (see “Logic’s Mixing Facilities” on page 191) and the section on
Faders and Level Adjustment (see “Level” on page 200).
Stereo recordings will normally be saved as Interleaved Stereo files. A stereo symbol,
consisting of two overlapping circles (see left image below), is shown beside the names
of Interleaved Stereo files (that appear as Regions) in the Arrange window.
Split Stereo Regions are indicated by a stereo symbol consisting of two adjoining
circles (see right image above).
You can freely mix both formats, even on the same track. We recommend that you use
the Interleaved Stereo format if your audio hardware supports it.
Split Stereo files require around twice the hard disk I/O performance of mono files.
Interleaved Stereo files, by comparison, only require about one and a half times the
throughput of Mono files.
Functions
Automatic Tempo Matching
Logic offers an automatic function that matches the length of a free-form musical
passage with the length of an audio Region. The length of the Region remains
constant, but the sequencer tempo is varied automatically, with the Region and
musical passage ending up exactly the same length.
To illustrate the use of this function, we’ll use a one-bar drum loop as an example:
Imagine you’ve recorded a drum loop live, or imported it from a sampling CD. You’ve
used the Audio window and Sample Editor to adjust the start and endpoints of the
audio Region, ensuring that the loop cycles perfectly, without any glitches.
Now, drag the drum loop into the Arrange window, where it appears as a Region. Make
sure that you place the front (left) edge of the Region at the start of a bar.