Splitting beats into clips

Clicking the Split Beats Into Clips button on the AudioSnap palette splits a selected AudioSnap-enabled clip into new clips starting at every enabled transient marker. The main reason you might want to do this is to align a clip with a new tempo or quantize it, without stretching the audio. Once you split a clip at its transients, you can move the new clips by dragging or quantizing so that they are aligned the way you want them to be. The advantage is that moving clips instead of transient markers does not stretch any audio, so that the original sound quality is unchanged. The possible disadvantage is that you can create gaps between the new clips when you move them. However, the Quantize, Groove Quantize, and Fade Selected Clips dialogs all have an option to automatically fill in the gaps. This is the Fill Gaps, XFade between Audio Clips option in the Fade Selected Clips dialog box, and is the Auto XFade Audio Clips option in the Quantize and Groove Quantize dialogs. Filling the gaps is accomplished automatically by “rolling out” the first clip’s right edge and the second clip’s left edge to create a crossfade. This option will often be used when quantizing drum parts, which results in smooth-sounding audio without introducing phase problems.

Note: When you align clips on multiple tracks, it is necessary to split and/or quantize all clips at the exact same position in order to avoid phase problems. In order to do so, it is necessary to establish a common, or master, transient pool that all tracks can reference. The Merge and Lock Markers command will use the transient pool as a reference, and insert identical transient markers on all selected clips. You can then use the Split Beats Into Clips button to split clips at audio beats.

To add markers at Pool lines

1.	Select the Smart tool in the Control Bar.

2.	Assign the track’s Edit Filter control to Audio Transients.

3.	Make sure that the Pool contains markers from at least one clip, or from the Time Ruler.

4.	Select the clips that you want to add markers to.

5.	Right-click a selected clip, and choose Pool > Apply transient pool markers on the pop-up menu.

Markers appear on the selected clips at Pool lines.

To split a clip at beats

1.	Select the clip(s) that you want to split.

2.	Press ALT+A to open the AudioSnap palette.

3.	Click the Split Beats into Clips button .

The clip’s beats are split into separate clips.

To split a clip, quantize it, and fill in the gaps

1.	The following picture shows a clip whose transient markers don’t line up with the measure lines:

2.	If we quantize it, the audio will stretch and we may or may not like the resulting sound. Let’s try splitting it, and quantizing the clips instead of the transients: click the Split Beats Into Clips button on the AudioSnap palette.

The clip splits at the transients, and only the first new clip is still selected:

3.	Let’s quantize the clips: drag through the clips to select them.

4.	Click the Quantize button in the AudioSnap palette.

The Quantize dialog box appears:

5.	Make sure that Audio Clip Start Times is selected, and that (for this example) Sixteenth is selected in the Duration field. Leave the Auto XFade Audio Clips option unchecked for now, and click OK. Let’s zoom in and look at the quantized clips:

6.	The start of each clip now lines up where we want it to, but there are gaps between some of the clips. Let’s undo what we just did (press CTRL+Z), and quantize again. This time, however we will enable the Auto XFade Audio Clips option in the Quantize dialog box, and click OK:

A. Crossfades

7.	Where the gaps were between clips, we now see crossfades. The default length of the crossfade is 20 milliseconds, but you can change that by entering a number in the XFade <number goes here> ms field in the dialog box.

8.	If you don’t want wide gaps to be filled in, you can enter a number of up to 200 milliseconds in the Max Gap field. Any gap that is wider than the number in this field will not be filled in.

If we wanted to drag the clips to new locations instead of quantizing them, we could fix any resulting gaps by selecting the clips that have gaps, and use the Track view Clips > Fade Clips command.

The Fade Selected Clips dialog box has the Fill Gaps, XFade between Audio Clips radio button, the XFade <number goes here> ms field, and the Max Gap field.

Figure 309. The Fade Selected Clips dialog box.

To fill in gaps with the Fade Selected Clips command

1.	Select the clips that have gaps you want to fill.

2.	Click the Track view Clips menu and choose Fade Clips to open the Fade Selected Clips dialog box.

3.	Enable the XFade between Audio Clips radio button, and set any options you want in the XFade <number goes here> ms field, and Max Gap field.

4.

Click OK.

 

See:

Using global tools on AudioSnap transient markers

Editing transient markers

Using the AudioSnap palette

Synchronizing audio and the project tempo

Fixing timing problems in audio clips

Extracting MIDI timing information from audio

Using the Pool

Algorithms and rendering