Adjusting volume levels
A clip's volume, or audio level, is one of its most obvious properties. You can hear it, and you can see it (in a few forms) in the Browser, Inspector, and Timeline. Audio levels have been discussed in passing throughout the book so far, so while this shouldn't be unfamiliar, there's definitely more to learn.
The unit used to describe audio volume is decibels, or dB, and it's used in both absolute and relative ways. However loud a clip is recorded, on a timeline it starts out at a neutral 0 dB. Adjustments made to that clip are relative, going from a louder +12 dB all the way down to the silence of -∞:
Figure 14.9: Audio volume levels on a few clips
When you play back a timeline, it's quite different. All sound playing at a particular moment is summed together, creating an absolute value, also measured in dB, and visible in the Audio Meters (⇧⌘8). These dancing meters show the total...
