Audio in Rich Media
Fixing and Enhancing Audio with Soundtrack Pro
This article is the fourth in a series exploring how audio can be integrated with other media to create richer, more dynamic journalistic features on news websites and beyond.
Adding audio is a great way to enhance traditional media and increase the impact of multimedia productions. So far in this series, we’ve gotten insights from some top professionals in the field, learned about essential equipment, and discovered some helpful field recording tips. Now let’s talk about shaping and enhancing audio in the production stage.
Once you’ve captured your audio, you need to prepare it for final delivery using an audio editing application such as Apple’s Soundtrack Pro, which is part of the Final Cut Studio suite of applications. Soundtrack Pro gives you everything you need to edit, process, and mix audio for rich media projects. Among other things, you can snip out unwanted sounds, clean up noise, rearrange or edit audio to fit a specific length, increase or decrease volume levels, and even enhance intelligibility — all tasks we’ll cover here. (In our next installment we’ll incorporate the doctored audio into a final mix.)
Because it’s designed to work with Final Cut Pro, Soundtrack Pro integrates seamlessly with video productions. But it’s also an excellent choice for self-contained audio projects and audio slideshows. As an example, we’ll be editing a short fictional interview with a self-styled “cryptobotanist” about her recent investigation into the properties of a most unusual plant. You can hear the original interview, warts and all.
Along with the actual interview audio, we recorded 30 seconds of ambient room sound, which we may use bits of to create smoother edits. We also recorded a narration and some ambient environment sounds to use in a later stage of production. We’ve already connected the digital recorder used for the interview and copied all the audio files to a folder on the computer (and made another “safety” copy in a second folder, just in case).
The Interface
We’re ready to start on the project — but first, let’s take a look at the Soundtrack Pro UI. When we open the program, the default view is for a Multitrack Project. But we’re currently working with an individual audio file, so instead we want the Audio File Project view. Under the File menu, select New, then Audio File. (We’ll return to the Multitrack Project view in the next article in this series.)
Soundtrack Pro's Audio File Project interface.
Soundtrack Pro’s Audio File Project interface is simple. The main window displays audio waveforms in a timeline, with a Play button and other controls beneath it. Above the timeline there’s a long, narrow window that displays your current location in the overall file. To the right, there’s a basic audio level meter.
Immediately to the left of the timeline is a list of Actions. This is where you can keep track of all the edits you make or any other processes you apply to the file. Above the Actions window is a ruler that displays various time-counter options, including seconds and minutes, samples, frames, and drop frame or non-drop frame timecode.
The small window in the upper left corner of the interface shows a thumbnail of any related video content you might be working on in Final Cut Pro. If you’re not working with video, you can set this window to display recording levels, file details, or a more in-depth audio meter instead.
Finally, in the lower left corner is a multi-tab window that provides access to a file browser, a search function, user-definable shortcuts to assets (Soundtrack Pro calls these “Favorites”), and an interface for choosing effects. Soundtrack Pro comes with a built-in library of useful effects, and you can also insert any other compatible audio processing plug-ins you might have on your computer.
The Browser is worth a closer look. This interface gives you access to all the files on your computer, so you don’t have to toggle back and forth between Soundtrack Pro and the Finder to locate your assets. You can “bookmark” a folder or even an individual file by selecting it and clicking on the “Add Favorite” button at the bottom right corner of the Browser window. Next time you want to locate something in this folder, just click on the Favorites tab in the Browser and choose the folder. This is a handy way to navigate back to a group of assets you’ll be using for a project without spending a lot of time clicking through menus.
Loading and Playing Files
Let’s proceed with the project. To locate the audio file we’ll be working with, just go to the Browser window and navigate to the folder where the interview audio was copied.
Double-click on the audio file in the Browser to open it. A dialog appears asking whether we want to create an Audio File Project (which allows us to edit nondestructively), or edit the original audio file (which makes permanent changes to the audio). We can also choose whether to work in mono or stereo, and select a sample rate. (The default is 48 kHz, which is the standard for most audio projects — but for audio-only projects we might select 44.1 kHz, the standard for audio CDs.)
The raw interview audio file loaded into Soundtrack Pro.
For this project, we’ll choose the nondestructive approach. In Audio File Project mode, each change we make to the audio file is recorded in the Actions list to the left of the timeline. To undo one of these edits later, just uncheck the box next to that action, and the file will automatically undo only that change. This workflow should feel familiar to anyone who’s worked with layers in applications like Photoshop.
To play the file, press the Play button in the transport area beneath the timeline, or press your computer’s space bar. The Play button (or space bar) also stops playback. By default, the audio file is set up for loop playback — that is, once it finishes playing the entire file (or a smaller selection you might have made) it immediately repeats from the beginning. To disable loop playback, click on the Cycle button (located on the transport, to the right of the Play and Go to End buttons).
Audio Editing Basics
Let’s start with a simple edit. At the beginning of the interview, there’s a loud click where the recorder was turned on, then some extra space before the voice comes in. We can delete this empty space by selecting it in the timeline and pressing the Delete key. The remaining audio automatically shifts to the left to fill the deleted space.
Selecting and cutting a click and extra space at the beginning of the audio file.
To select a section of audio, click-hold on the waveform where you’d like the selection to start, then drag to the location where you’d like it to end. Alternately, you can click on the desired starting point, hold down the Shift key, and click again on the desired ending point.
If you find that you haven’t selected quite enough audio (or you’ve selected too much), hold down the Shift key and click on the correct end location to add to (or reduce) your current selection without losing the previously selected area.
When selecting regions to cut, copy, paste, or delete, it’s a good idea to zoom the view in closer to make sure your selection is in the right place. To zoom in, type Command - Shift - =, and to zoom out, type Command - - key. You can also zoom in and out quickly by dragging the Zoom cursor beneath the Actions list, or by dragging the right and left edges of the slider bar at the bottom of the timeline. There’s another tool for getting up close as well: the little magnifying glass icon above the time ruler lets you zoom in without losing your selection or moving the timeline.
You can zoom in close to make edits...
Or zoom out to see the entire file.
Making Audio Flow
The most important part of editing audio is listening. Use headphones, or monitor with good-quality speakers in a quiet environment. After each edit, listen carefully to the audio from a few seconds before the change to a few seconds after. Not only do your actual cuts and transitions need to sound smooth — the entire phrase should flow properly. Removing a few words can sometimes make the rest of a sentence sound rushed, stilted, or incomplete. Periodically listen to the flow of the entire section you’re working on to make sure your final audio file sounds natural, convincing, and glitch-free. The smallest flaws can snag listeners’ ears and distract them from the content you’re presenting.
The interview audio with questions and other distracting elements edited out. Note the series of "Deleted Audio" events in the Actions list.
Remember, breaths and pauses are an essential part of human speech. Try not to cut out breaths between words — without them, your audio will sound vaguely disturbing. Also guard against making edits in the middle of breaths, and beware of cutting off breaths and other vocal sounds prematurely at the ends of words. Allow a bit of space for the voice to trail off at the end of a phrase. If there’s an especially loud breath, consider lowering the amplitude (for more on this, see “Adjusting Levels” below), or replace it with a quieter breath of similar length from another location in the file.
The sound of the room in which a recording was made is almost as important as the words or other sounds in the foreground. Don’t strip out all the spaces between words and replace them with absolute silence; this sounds unnatural and distracting. If a phrase seems rushed, or you want to add a bit of emphasis, try inserting a second or two of empty space to give it some “breathing room.” Borrow a bit of room sound from elsewhere in the file, or copy and paste it from the dedicated “room sound” recording you had the foresight to capture at the interview.
