Organizing Sounds on the Timeline

The Flash Player can play several sound layers at once within a Flash movie; each layer functions like a separate sound channel, and Flash mixes them on playback. This capability of Flash might be considered a built-in economy sound mixer. There is, however, a practical limit because each sound layer potentially increases the movie's file size, while the mix of multiple sounds may burden the computer it's being run on.

New Feature 

Flash Player 8 and Flash 8 movies can play up to 32 simultaneous sound channels. In older versions of the Flash Player, you are limited to 8 simultaneous sound channels.

Enhanced Viewing of Sound Layers

Because sound is different from other types of Flash content, some users find that increasing the layer height of the sound layers eases working with multiple sounds in the timeline. That's because a taller layer height provides a better visual cue due to the unique waveforms of each sound. To increase the layer height for individual layers, follow these steps:

1. Right-click (or Control+click on the Mac) the layer in the Timeline window, and then choose Properties from the contextual menu.

2. At the bottom of the Layer Properties dialog box, change the layer height from the default 100 percent to either 200 or 300 percent.

   Note that these percentages are relative to the settings chosen in the options menu (located at the top-right corner) of the Timeline window.

Cross-Reference 

For more information on the Timeline window, see Chapter 4, "Interface Fundamentals." For an actual example of this enhanced viewing, open the file enhanced_view.fla, located in the ch15 folder on the CD-ROM.

Tip 

Your movie's frame rate, as specified in the Document Properties dialog box (Modify ð Document), affects the number of frames that a sound occupies on the timeline. For example, at Flash's default setting of 12 frames per seconds (fps), a 30-second sound clip extends across 360 frames of the timeline. At 18 fps, the same 30-second clip expands to 540 frames — but in either case, the time length of the sound is unchanged.

Organizing Sound Layers with a Layer Folder

Flash MX introduced a new organization tool for layers in any timeline: layer folders. To nest sound layers in a layer folder, create a new layer folder and then drag each of the sound layers to the folder. As you drop each layer on the folder, it will nest within the folder.