Specifications

Pro Tools Reference Guide608
Mixer Usage Guidelines
The following conditions apply to mixing with
Pro Tools TDM systems.
One DSP chip is automatically dedicated to
mixing in the TDM environment.
As you reach the basic mixer limits for a single
DSP chip, the system will automatically begin
allocating DSP resources from another chip (if
available), making it unavailable for plug-ins.
Each bus or send connection requires DSP to
mix signals. This means that each send or Aux-
iliary Input that you create will require DSP
power to mix the results.
On Pro Tools|24 systems, the 16-bit Opti-
mized Mixer can power more channels per DSP
chip than the 24-bit Optimized Mixer plug-in.
There may be cases where using the 16-bit Opti-
mized mixer will help conserve enough DSP
power to allow for additional plug-ins.
On Pro Tools|24 MIX systems, there is no ad-
vantage to using the 16-bit Optimized mixer, so
you should always use either the Surround
mixer, or the 24-bit Optimized mixer.
DSP Usage with TDM Plug-Ins
Some basic guidelines for DSP usage on
Pro Tools systems follow:
TDM-equipped systems running Pro Tools 4.3
or higher software use Digidesign’s MultiShell
technology, that lets any MultiShell compatible
plug-in share DSP chips on both HD Core and
Process cards (in a Pro Tools HD-series system),
or both MIX cards and DSP Farm cards (in a
MIX-series system). Up to five types of Multi-
Shell compatible plug-ins can share a single DSP
chip.
Stereo DSP plug-ins generally use up twice as
much DSP as mono plug-ins.
Master Faders don’t require additional DSP.
Use them freely to control submix levels,
send/bus output levels, and the master output
level of your session.
The session templates provided with your sys-
tem include several useful preconfigured session
setups that make efficient use of DSP resources.
If your computer has unused slots, you can al-
ways increase your available DSP resources by
adding additional HD Accel or HD Process cards
(to a Pro Tools HD-series system), or MIX Farm
or DSP Farm cards (to a Pro Tools MIX-series sys-
tem or Pro Tools|24 system).
Refer to the DigiRack Plug-Ins Guide for de-
tails on MultiShell plug-ins.