User Manual

Chapter 6: System Setup 65
This option is only available if the Ignore Errors
During Playback/Record option is enabled and
the Pro Tools system you are using requires ad-
ditional buffering for error suppression, as fol-
lows:
•Windows:
• Mbox Pro and Mbox 2 Pro
• All Pro Tools systems with M-Audio devices
•Mac:
• 003 family devices
•Eleven Rack
• Mbox family devices
• Digi 002 and 002 Rack
• All Pro Tools systems with M-Audio devices
• Pro Tools Aggregate I/O
Number of Voices
(Pro Tools HD Only)
On Pro Tools|HD systems, the Number of Voices
setting in the Playback Engine lets you control
the number of available voices and how those
voices are allocated to DSPs in your system. For
example, the default number of voices on a
Pro Tools|HD 1 system is 48 voices, using one
DSP (at sample rates of 44.1 kHz or 48 kHz).
Changing the number of voices affects
DSP usage, the total number of voiceable tracks,
and overall system performance.
Depending on the session sample rate and the
number of Pro Tools|HD cards in your system,
there are different choices for voice count. For
voice limits on different Pro Tools|HD systems,
see “Playback, Recording, and Voice Limits with
Pro Tools HD” on page 44.
To change the Number of Voices and DSP to
allocate for voicing:
1 Choose Setup > Playback Engine.
2 Select the number of voices and DSPs to allo-
cate for voicing by selecting a value from the
Number of Voices pop-up menu as follows:
• Select minimum voice numbers if you are
using high-bandwidth PCI or PCIe cards
(such as video capture cards) along with
your Pro Tools|HD cards. These settings
place the lightest processing load on each
allocated DSP chip, but generally require
more DSP chips be dedicated to voicing
and mixing (leaving fewer available for
plug-ins).
• Select medium voice numbers when your
Pro Tools|HD cards are in an expansion
chassis, or when you are using other PCI or
PCIe cards along with Pro Tools|HD cards.
These settings generally provide an opti-
mum balance between number of chips
needed for voicing, and the processing load
placed on each.
• Select higher voice numbers when your
Pro Tools|HD cards are the only PCI or PCIe
cards in your computer, or when you are
using an expansion chassis to run higher
track counts (such as 64 tracks at 96 kHz)
and you want more voices per DSP (such as
16 voices per DSP at 96 kHz). These settings
use fewer DSP chips for mixing (leaving
more available for plug-ins) but place the
highest processing load on each.
3 Click OK.