DigiDesign DigiRack Plug-ins Manual page 16

DSP Sharing Between TDM Plug-ins
With Digidesign's MultiShell™ II technology,
different types of TDM plug-ins can share the
same DSP chip at the same time. This lets you si-
multaneously use a greater variety of plug-ins by
efficiently managing the DSP available on each
chip in your system.
To take advantage of this capability, plug-ins
must be MultiShell II compatible. All
DigiRack TDM plug-ins with the exception of
Pitch are MultiShell II compatible.
Some third-party plug-ins may not be Multi-
Shell II compatible. To check compatibility,
contact the manufacturer.
RTAS Plug-ins
RTAS plug-ins rely on and are limited by the pro-
cessing power of your computer's CPU. The
more RTAS plug-ins you use concurrently in a
session, the greater the impact it will have on
other aspects of your system's performance,
such as maximum track count, the density of
edits possible, and latency in automation and
recording.
The CPU meter in the System Usage window
(Window > System Usage) shows how much of
your computer's processing power is currently
being used by Pro Tools, and how much is still
available.
For more information on the System Usage
window, see the Pro Tools Reference Guide .
10 DigiRack Plug-ins Guide
Improving RTAS Plug-in
Performance
You can increase the number of RTAS plug-ins
your system can use concurrently by increasing
the Hardware Buffer Size and CPU Usage Limit.
Hardware Buffer Size
The Hardware Buffer Size (H/W Buffer Size) con-
trols the size of the hardware cache used to han-
dle host processing tasks such as monitoring la-
tency and using Real-Time AudioSuite (RTAS)
plug-ins.
Lower Hardware Buffer Size settings reduce
◆
monitoring latency, and are useful when you are
recording live input.
Higher Hardware Buffer Size settings provide
◆
more audio processing and effects, and are use-
ful when you are mixing and using more RTAS
plug-ins.
In addition to causing slower screen re-
sponse and monitoring latency, higher
Hardware Buffer Size settings can affect the
accuracy of plug-in automation, mute data,
and timing for Instrument or MIDI tracks.
To change the Hardware Buffer Size:
Choose Setup > Playback Engine.
1
From the H/W Buffer Size pop-up menu, select
2
the audio buffer size, in samples.
Click OK.
3