Use beat mapping on audio regions
Beat mapping audio regions works similarly to beat mapping MIDI regions. If the audio regions don’t contain tempo information, they must be analyzed to find transients (short amplitude peaks, usually at rhythmically prominent positions), which can be mapped to a ruler position, before you can use them for beat mapping.
Transients appear as blue vertical lines in the lower part of the Beat Mapping track, aligned to peaks in the audio waveform. If no transients are visible on the selected audio regions when you open the Beat Mapping track, analyze the regions before applying beat mapping.
Detect transients in audio regions
Select the regions to analyze, then click the title “Beat Mapping” in the Beat Mapping track and choose Analyze Transients from the shortcut menu.
After the regions are analyzed, the transients appear as blue vertical lines in the lower part of the Beat Mapping track.
Tip: It may be difficult to identify transients if the waveform overview is too small. If transients are hard to see, click the Waveform Zoom button in the Tracks area menu bar to visually resize the waveform in the Beat Mapping track.
The remaining steps for beat mapping audio regions are the same as for MIDI regions. To follow those steps, see Use beat mapping on MIDI regions.
There are a number of ways to improve the beat mapping accuracy of audio regions. When you choose Analyze Transients, those transients above a certain threshold are displayed. You can adjust the threshold using the Minus and Plus (–/+) buttons in the Beat Mapping track.
Increasing the number of transients can be useful when beat mapping regions with less distinct accents—such as soft drums in a loud mix. However, a high setting can result in extraneous transients, with no real meaning for the rhythmic structure, being displayed. In general, it’s better to begin with a lower setting, and move to a higher setting only if transients are missing for obvious rhythmic elements in the music.
Sometimes, your MIDI recordings may contain note events that fall on musically meaningful positions, and should not be affected by beat mapping applied to audio recordings. In this case, you can choose the Protect MIDI option to keep existing MIDI events at their current ruler positions when beat mapping audio regions.
You can also make beat mapping easier by moving one or multiple selected audio regions, so that the first transient marker in any of the regions is located on the nearest whole beat position.
Change the threshold of transients displayed
Do one of the following:
To decrease the number of transients displayed: Click the Minus button (−) in the header of the Beat Mapping track.
To increase the number of transients displayed: Click the Plus button (+) in the header of the Beat Mapping track.
Protect MIDI events from being beat mapped
Click the title “Beat Mapping” in the Beat Mapping track, then choose Protect MIDI from the shortcut menu.
Move the first transient marker in a region selection to the nearest whole beat position
Control-click the beat mapping header, then choose Move Selection with First Transient to Nearest Beat from the shortcut menu (or use the corresponding key command).
The first transient marker in the region selection is moved to the nearest whole beat position, with all selected regions moving with it.