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Pro Tools Reference Guide 580
Offsetting MIDI Tracks
Pro Tools can offset MIDI tracks globally or indi-
vidually.
Global MIDI Playback Offset
Pro Tools offers a MIDI offset preference that al-
lows MIDI and Instrument tracks to play back
earlier or later (than audio tracks) by a specified
number of samples. The offset affects playback
only and does not alter in any way how MIDI
data is displayed in the Edit window.
This capability is provided in large part to com-
pensate for the audio monitoring latency in
Pro Tools LE. If you are monitoring the output
of external MIDI instruments with an external
mixer or sound system (or headphones), there is
no latency. If, however, you are monitoring the
output of your MIDI devices through a
Pro Tools LE interface (such as Mbox 2), your
MIDI tracks sound slightly later than your audio
tracks. The larger the setting for the H/W Buffer
Size (128, 256, 512, or 1024 samples), the larger
the latency.
By configuring the Global MIDI Playback Offset,
you can align your MIDI tracks to play back
slightly earlier (by a specified number of sam-
ples), thereby compensating for any latency
when monitoring audio in Pro Tools LE.
To configure the Global MIDI Playback Offset:
1
Choose Setup > Preferences and click the MIDI
tab.
2
For the Global MIDI Playback Offset option,
enter the number of samples (–10,000 to
10,000) for the offset. A negative value causes
the MIDI tracks to play back earlier than the au-
dio tracks; a positive value causes the MIDI
tracks to play back later.
To allow for monitoring latency in Pro Tools LE,
set the offset to a value that is roughly equiva-
lent to the H/W Buffer Size.
3
Click OK.
Individual MIDI and Instrument Track
Offsets
You can offset individual MIDI and Instrument
track offsets in Pro Tools to compensate for de-
lays in MIDI devices (the time it takes to trigger
events on a sampler or synth).
For example, if you have some kick drums that
are being played by an audio track in Pro Tools
and want them to be exactly synchronized with
kick drums that are being played by a MIDI de-
vice, you may need to use a MIDI offset. In this
example, it will usually take at least 5 ms to trig-
ger the MIDI notes, and it could take even
longer, depending on the MIDI device.
You can measure the latency for a MIDI device
assigned to a MIDI track by recording its audio
output back into Pro Tools. Compare the sam-
ple locations for the recorded audio events
against the original MIDI notes to calculate the
latency.
With Pro Tools HD, when Delay Compen-
sation is active, MIDI and Instrument
tracks are automatically delay-compen-
sated to provide low latency monitoring. For
more information, see “Delay Compensa-
tion for MIDI” on page 659.
The Global MIDI Playback Offset can also
be set from the MIDI Track Offsets window.
You can also apply MIDI Real-Time Proper-
ties delay to offset MIDI (see “MIDI Real-
Time Properties” on page 607).