To set loop begin and end times, and turn on loopplay:

Loop mode
The loop mode function lets you define a section of
your session and automatically loop playback of that
section over and over. This is particularly useful for
practicing along with a short section of a session in
preparation for recording a track, or for evaluating
potential loops for arrangement purposes.
To set loop begin and end times, and turn on loop
play:
1. Scrub the small begin tape counter in the
Transport window to the desired loop start point.
– You can scrub the counter by clicking and holding
down the mouse over the counter. When the
cursor changes to right/left arrows, drag to the
right (forward) or left (backward) to set the exact
point in the recording. Scrubbing this way will play
audio as the counter moves. If you wish to slide
the counter value without hearing audio, hold
down the Shift key. Then click and drag the
mouse over the begin tape counter. To set the
loop time with the keyboard, hold down the
Command key and click the begin counter. Then
use the dialog to set your time.
– You can also click the Begin and End buttons to
enter the current master counter time while a
session is playing back. After the times have been
picked up, you can fine tune the begin and end
times by scrubbing. Command-click the Begin and
End buttons to transfer their times to the
Transport window’s master counter.
2. Scrub the small end tape counter to the desired
loop end point.
3. Click the Loop button.
4. Click the Transport’s Play button to play back the
loop. Click the Stop button to halt playback.
Loops may not be shorter than 0.5 seconds. If
you try to set a loop that is shorter than half a
second, Deck will automatically turn off the
loop.
There are a number of tools that greatly enhance the
usability of Loop mode. You can automatically move
the selection range (in the Tracks window) to the
begin and end counters using the Option > Selection
Tools > Set Punch Times From command (or move
the other direction using the Set from Punch Time
command). You can also use other commands on this
submenu to automatically select the waveform range
between the begin and end times indicated in the
Transport window. For more information see Chapter
9, “Deck Reference.” Finally, when the Track window
is open, you can press C on your keyboard at any time.
This issues a Cue command, which automatically sets
the Transport window’s start and end times to match
the current selection and turns on Loop mode.
Option-C turns Loop mode off.

Knowledge Base