Specifications

Pro Tools Reference Guide434
Configuring Pro Tools
Hardware I/O for Recording
Before you start recording, make sure your
Pro Tools system hardware is connected and con-
figured properly. For details on connecting
Pro Tools to your studio and configuring your
Hardware in the Hardware Setup dialog, see the
User Guide that came with your system. For in-
formation on how to route signal paths in
Pro Tools, see Chapter 7, “I/O Setup.”
Input Connections and Audio
Levels
Avid HD audio interfaces operate as line-level de-
vices and offer no pre-amplification. Low-level
sources like microphones and electric guitars need
to be pre-amplified. You can do this with a quality
mixing board or dedicated preamp (such as PRE).
003 Rack+ has eight inputs with preamps, to which
you can connect low-level signals.
003, 003 Rack, Digi 002, and Digi 002 Rack have
four inputs with preamps, to which you can con-
nect low-level signals, and four additional line-
level inputs with switchable gain.
Eleven Rack has one Mic input with a preamp and
1 instrument-level Guitar input with a special vari-
able-impedance circuit called True-Z (for more in-
formation, see the Eleven Rack User Guide.)
Mbox (3rd generation), Mbox 2, Mbox Pro, Mbox
2 Pro, Mbox Mini, and Mbox 2 Mini each have two
inputs with preamps, to which you can connect
low-level signals.
For all systems, volume and pan controls for tracks
in Pro Tools only affect monitoring levels—not
the recording input gain. The LED meters on
Pro Tools audio interfaces indicate both full-code
(highest level before clipping) and true clipping of
Pro Tools output signals. The on-screen meters in
Pro Tools indicate only true clipping.
Digital Clipping
Clipping occurs when you feed a signal to a re-
corder or mixer that is louder or “hotter” than the
device allows. On many analog tape decks, a little
clipping adds a perceived warmth to the sound due
to tape compression. In digital recording, however,
clipping causes digital distortion, which is undesir-
able and should always be avoided.
Set Input Levels
When you feed a signal into any audio recording
system, including Pro Tools, make sure to adjust
the input level to optimize the dynamic range and
signal-to-noise ratio of the recorded file. If the in-
put level is too low, you will not take full advan-
tage of the dynamic range of your Pro Tools sys-
tem. If the input level is too high, the waveform
can clip and distort the recording. Set the input lev-
els high, but not high enough to clip.
As a general rule of thumb, try to set levels so that
they peak within –6 dB to –12 dB on the
input meter without triggering the clipping indica-
tor on your audio interface. Depending on the type
of material you are recording and its dynamic
range and peak content, you may want to record
with higher or lower levels.
You can display a track’s input levels in its Vol-
ume/Peak/Delay indicator. Normally, this indica-
tor is set to be a Volume indicator. When you
change it into a Peak indicator, it can function as a
headroom indicator based on the last peak play-
back level.
PRE can be remote-controlled from within
Pro Tools sessions.