User Manual

AUDIO BEATS AND TEMPO DETECTION
661
Beat velocity
In addition to placement, beats are also analyzed
for their strength, relative to the other beats around
them. The strength of the beat is represented by the
beat’s velocity handle (Figure 53-2), which can be
adjusted by dragging the handle vertically. Move
up the slider to increase velocity; move it down to
lower velocity. Beat velocity translates into MIDI
note-on velocity when copying beat data as MIDI
using the Copy Beats as MIDI command in the
Audio menu and Beats menu (Figure 53-2), or
when extracting the audio’s groove using the Create
Groove command (Region menu).
Disabled beats
There may be times when you wish to disable a
beat. When a beat is disabled, its location is
remembered, but it is ignored for all beat- and
tempo-related operations. You can re-enable it at
any time by selecting it and choosing Tog g le
Selected Beats in the Beats menu, as explained in
the following sections.
To disable a beat, click it with the Mute tool in the
Tool palette (Figure 36-1 on page 331).
BEATS MENU
The Beats menu (Figure 53-2 on page 660) offers
several convenient features for working with
soundbites.
Find Beats
The Find Beats command opens a window that
allows you to add beats to selected soundbites,
detected using Digital Performer’s beat detection
algorithm. Once a soundbite has been selected, the
algorithm will find the beats and display a preview.
Click Apply to save these beats to the soundbite.
Figure 53-3: Find Beats.
The slider in the window adjusts the sensitivity
setting, which alters how sensitive the beat
detection algorithm is when finding beats in audio.
A low sensitivity setting means the beat detector
will detect fewer beats, and a high sensitivity
setting will lead to more beats being found. Move
the slider to the right to increase the sensitivity
setting, or move it to the left to lower it: the preview
will update the results accordingly. After clicking
Apply the new sensitivity setting will be
remembered so that any future beat detection on
that audio file will use the updated sensitivity level
by default.
There are situations in which it is useful to alter this
setting. For example, in a live recording, audience
noise or chatter could be mistaken for beats. In this
case a lower sensitivity would remove these false
positives. As another example, increasing the
sensitivity would yield better results in recordings
with very quiet transients.
In general, lowering the sensitivity setting reduces
the detection of false positives while increasing the
sensitivity will find more beats.
The Find Beats command is also available in the
Audio menu so that you can use it on selected
soundbites in the Sequence Editor, too.
Clear Beats
The Clear Beats command removes all the beats
from the audio file.