DigiDesign Mbox 2 Pro Getting Started Manual page 23

To change the Hardware Buffer Size:
Choose Setup > Playback Engine.
1
Playback Engine dialog for Mbox 2
From the H/W Buffer Size pop-up menu, select
2
the audio buffer size, in samples.
Click OK.
3
RTAS Processors
The RTAS Processors setting determines the
number of processors in your computer allo-
cated for RTAS plug-in processing.
With computers that have multiple processors,
or that feature multi-core processing or hyper-
threading, this setting lets you enable multi-pro-
cessor support for RTAS processes. Used in com-
bination with the CPU Usage Limit setting, the
RTAS Processors setting lets you control the way
RTAS processing and other Pro Tools tasks are
carried out by the system.
A higher number of processors reserves more
◆
CPU processing capacity for RTAS plug-in pro-
cessing. This is useful for sessions with large
number of RTAS plug-ins.
A lower number of processors leaves more
◆
CPU processing capacity for automation, screen
redraws, and video playback in Pro Tools, or for
other application running at the same time as
Pro Tools.
To set the number of RTAS Processors:
Choose Setup > Playback Engine.
1
From the RTAS Processors pop-up menu, select
2
the number of available processors you want to
allocate for RTAS plug-in processing.
Click OK.
3
If using a single processor computer, be sure
to check the section "Disabling Hyper-
Threading" on page 12 for tips on maximiz-
ing performance.
CPU Usage Limit
The CPU Usage Limit controls the percentage of
CPU resources allocated to Pro Tools host pro-
cessing tasks. Used in combination with the
RTAS Processors setting, the CPU Usage Limit
setting lets you control the way Pro Tools tasks
are carried out by the system.
Lower CPU Usage Limit settings limit the ef-
◆
fect of Pro Tools processing on other CPU-inten-
sive tasks, such as screen redraws, and are useful
when you are experiencing slow system re-
sponse, or when running other applications at
the same time as Pro Tools.
Higher CPU Usage Limit settings allocate
◆
more processing power to Pro Tools, and are
useful for playing back large sessions or using
more real-time plug-ins.
The maximum available CPU Usage Limit de-
pends on the number of processors in your com-
puter and on the number of processors you
specify with the RTAS Processor setting. This
value can be up 99 percent for single-processor
computers or 90 percent for multi-processor
computers.
Increasing the CPU Usage Limit may slow
down screen response on slower computers.
Chapter 3: Windows Configuration 15