Visual Editing in the Spectral Frequency Display
The Spectral Frequency Display in Adobe Audition is beautiful to look at, to be sure. But it gives you insight into your audio clips that a waveform view can’t match. For example, in the Spectral Frequency Display, you can see individual harmonics and overtones, and their relative strength. You can see noise. Best of all, you can edit what you see using graphic editing tools with which you’re probably already familiar, and make edits to your audio with near-surgical precision.
If you’re dazzled by brilliant colors, you might miss some of the more useful tools offered by the Spectral Frequency Display. While in the Waveform Editor, let’s take a look at several different types of sound in the Spectral Frequency Display. Frequencies are displayed from low at the bottom to high at the top, and in all cases, the yellower the color, the louder the sound.
If you wanted to zoom in on those lower frequencies in order to edit them, you certainly could. But there’s a more powerful tool available to help you with this. Option-click (Mac) or right-click (PC) in the vertical ruler on the right, and the following menu appears. From this menu you can configure the vertical scale of frequencies from all linear to all logarithmic, which will make the lower frequencies much more visible. You can also adjust the resolution, to make the Spectral Display more precise.
The following screen shot shows the exact same audio file as in Example 1, but with Full Logarithmic selected as the scale in the vertical ruler. Note the huge difference in the appearance of the loudest sounds, which for the most part includes the fundamental pitch of an instrument or voice, or the main element in noise. Much more information about these particular sounds is revealed when the scale is logarithmic: You can see the individual notes of the bass in the power trio, the dialogue, and the tuba. You can see the Doppler effect of a passing jet in the airport taxiway. In all cases, you can clearly see frequencies even below the fundamentals.
With the logarithmic setting, most of the sounds that concern audio editors stand out in relief: fundamentals, overtones, and even noise. The Marquee Selection tool, Lasso Selection tool, Paintbrush Selection tool, and Spot Healing Brush tool are very easy to use and are uniformly effective with all of these sonic elements. But there are a couple of other tools that come up in a contextual menu when you option-click or right-click on the Spectral view itself, such as Capture Noise Print (the first step to automatically removing noise from a clip) and Auto Heal Selection (dramatically reduces a particular sound or noise without eliminating the surrounding background ambience).
The copy command works just as you’d think, letting you make a copy of any area you can select. What do you do with copies of audio data? Do some sound design by pasting part of one sound into another, for one thing. In the following screen shot, we copied the approaching police siren on the left (the oscillating pitch of which is highly), and then pasted it onto the dialogue clip. The result: A dialogue with a passing siren, but without the whoosh of the tires and body noise.
You can make even more precise selections with the Lasso Selection or Paintbrush Selection tools. In the following screen shot we use the Lasso Selection tool to select and delete the annoying squeak of a shutting door without disturbing the shutting sound. The result: a door that shuts without squeaking.
To learn more about the power of the Spectral Frequency Display, watch Jason Levine’s excellent video demo by clicking on this link.