Setup guide

Pro Tools|HD Setup Guide44
Number of Voices
The Number of Voices setting lets you control
the number of voices available on your system.
For example, the default number of voices on an
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 current sample rate and the
number of cards in your system, and whether
you are using an expansion chassis, you will
have different choices for voice count.
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 choosing a value from the
Number of Voices pop-up menu.
• Select minimum voice numbers if you are
using high-bandwidth PCI or PCIe cards
(such as video capture cards) along with
your Digidesign cards. These settings place
the lightest processing load on each allo-
cated DSP chip, but generally require more
DSP chips be dedicated to voicing and mix-
ing (leaving fewer available for plug-ins).
• Select medium voice numbers when your
Digidesign cards are in an expansion chas-
sis, or when you are using other PCI or PCIe
cards along with Digidesign cards. These
settings generally provide an optimum bal-
ance between number of chips needed for
voicing, and the processing load placed on
each.
• Select higher voice numbers when your
Digidesign 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.
Default Sample Rate
The Sample Rate setting determines the default
sample rate when you create a new session. This
setting is available only when there is no session
open. Otherwise, the current session sample rate
is displayed, but cannot be changed.
For additional information on voice count,
refer to the Pro Tools Reference Guide.
Number of Voices menu (HD|1-equipped system)
The Sample Rate setting can affect the
number of available voices.