Apple Logic Express 7 - Manual (Page 148)

148 Chapter 4 Audio in the Arrange Window
There are two parameters:
Crossfade Time [ms]: This is the length of the entire crossfade. To switch off the
crossfade, set this value to zero.
Crossfade Curve: To obtain a linear crossfade, set this value to zero. Other values
(positive or negative), produce various exponential fades. The fade-outs and fade-ins
are always symmetrical, to avoid deviations in level. The preset values are: Time =
20 ms, Curve = 0 (linear).
The graph shows the actual shape of the crossfade; the original algorithms are also
used to calculate the curve display. Values over about 250 ms are scaled in the graph,
to ensure that the entire crossfade is visible.
Freeze
The Freeze function saves almost 100% of the CPU power used for software
instruments and effect plug-ins. You can apply it, individually, to audio or Audio
Instrument tracks.
Concept
Internally, Freeze performs individual offline bounce processes for each “frozen” track.
All plug-ins of a track (including software instrument plug-ins, if applicable, along with
all related automation data) are rendered into a “Freeze file”.
As long as a track is frozen—following the freeze process—the freeze file will play back
in place of the original track (and its CPU-hungry plug-ins). The original track and plug-
ins are temporarily deactivated, and use no CPU resources.
Due to technical reasons, the Freeze function is not available for the tracks of DSP-
based audio hardware systems (such as ProTools), tracks that use plug-ins calculated on
DSP cards (Powercore, UAD-1, Pulsar, and so on) or tracks that use external signal
processing devices via the I/O plug-in. You can, however, freeze tracks that use Sends to
Busses—with DSP-based or I/O plug-ins used on the busses.
The Freeze function always bounces the complete channel signal. If you are using more
than one track for the same audio or instrument channel in the Arrange, then all
(sub)tracks of this channel will be frozen, and cannot be edited independently.
When to Freeze a Track
In real-life situations, Freeze allows you to:
• use additional plug-ins or software instruments in further audio or instrument tracks,
which would normally not be possible as it would exceed the CPU processing limits
of your computer.
• Play back songs created on computers with greater CPU power.