DigiDesign Pro Tools 8.0 Reference Manual page 686

The following table lists the number of ticks for
each of the main note sizes:
Note Value
1/2 note 1920
1/4 note 960
1/8 note 480
1/16 note 240
1/32 note 120
1/64 note 60
Tick- and Sample-Based
Timebases
Pro Tools lets you set any track timebase to ei-
ther sample-based or tick-based.
Audio tracks in Pro Tools are sample-based by
default. This means that audio regions and
events are located at specific sample locations,
and they do not move from that location if the
tempo changes in the session—even though
their bar and beat locations do change.
MIDI and Instrument tracks in Pro Tools are
tick-based by default. This means that MIDI re-
gions and events are located at a specific bar and
beat locations, and they do not move from that
location if the tempo changes in the session—
even though its sample location does change.
Sample-Based Audio and MIDI
With a sample-based audio track, all audio re-
gions in the track have an absolute location on
the absolute Timeline (for example, on the Sam-
ples or Minutes:Seconds Timebase ruler). Audio
stays fixed to the sample time, regardless of any
tempo or meter changes occur in a session.
668 Pro Tools Reference Guide
Normal Dotted Triplet
2880 1280
1440 640
720 320
360 160
180 80
90 40
On sample-based MIDI and Instrument tracks,
all MIDI events in the track have an absolute lo-
cation on the absolute Timeline (for example,
on the Sample or Minutes:Seconds Timebase
ruler). MIDI events stay fixed to the sample
time, regardless of where tempo or meter
changes occur in a session.
Tick-Based Audio and MIDI
Tick-based audio is fixed to the relative time of
the Bars|Beats Timebase ruler, and moves rela-
tive to the sample Timeline when tempo and
meter changes occur. However, MIDI and Elastic
Audio events, and tick-based audio regions
(non–Elastic Audio) respond differently to
tempo changes in respect to duration. MIDI
note events and Elastic Audio regions change
their duration when tempo is adjusted, while
non–Elastic Audio audio regions do not. Tempo
changes affect only the location of the begin-
ning (or sync point) of each audio region in a
tick-based (non–Elastic Audio) audio track.
You can select whether a track is sample-based
or tick-based when it is created, or change time-
bases later.
To have all new tracks default to tick-based,
enable the New Tracks Default to Tick
Timebase option in the Editing Preferences.
Tick-Based Elastic Audio
Tick-based Elastic Audio tracks automatically
apply Real-Time (or Rendered) Elastic Audio
processing (TCE) when changing tempo. For
more information, see "Tempo Changes and
Tick-Based Elastic Audio Tracks" on page 674.