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DAW Basics: Collecting, Combining, and Optimizing Files

By Jon Chappell



Selecting start and end points, and defining the "silence gap" in Pro Tools. (Click images to englarge.)


DAWs are wonderfully creative tools for composing, arranging, capturing improvs, and mashing loops, but they’re also really good for just doing workaday tasks like audio editing, file clean-up, and track assembly. Though it might seem like overkill to launch a DAW to perform a basic task—using a sledgehammer to crack a walnut—it’s sometimes the quickest and simplest way to get something done.


I often encounter people who traffic in lots of audio files (mp3’s, waves) and who have all sorts of housekeeping needs but don’t know that a DAW could serve as their Swiss Army Knife, handline all their needs. You don’t need to access a DAW’s deepest editing depths to make good use of one, and basic housekeeping and management is something full-fledged DAWs do particularly well—much better than programs like Windows Media Player and GarageBand.



If you have a lot of small but related files, you make your life easier by consolidating them into a single file. Then just break them out as discrete file names on an as-needed basis by going into the master file and generate the smaller subfiles on the fly. For example, if you have collected a bunch of field recordings of a similar type, whether they’re bird calls, crowd noises, or snare drum samples, you should gather them in a DAW project where they call all be trimmed, optimized, and loudness-normalized together. Think of them as a single listening experience where you don’t want varying levels between them.


You can also structure them such that all start with no delay or lag time, and all have a uniform interval (usually three seconds) after the last sound dies away. This will be especially handy if you're creating a CD.



Moving all files of a similar kind into a single track can be thought of as “track hosting.” Start by opening up a new file in any DAW (I’ll use Pro Tools here, but the steps are similar in other DAWs), and create one or two stereo tracks. Even if the source is mono, your resulting output should be in a stereo format, and if you use any kind of ambient effect, such as reverb, you’ll also want that in stereo.


Import your audio file by selecting the Import command. A navigation window opens up. In my example, I’ve selected two files, one called Adele.wav and the other JerryReed.mp3. DAWs allow you to mix audio files of different formats and sampling rates by converting them for you in the import process. Note that in Figure 1 below, the DAW flags the mp3 as needing conversion before it will work in this project (see text in red oval). This window also shows you other specs of the audio you’re importing.


Fig. 1




You can assemble all your audio in one track or two. If you use two (as I do), you just have to make sure the settings (level, pan, choice of plug-ins, etc.) are exactly the same between them. In Figure 2, you see what my two test files look like in the track or project window after importing. Here, the different coloring (blue for the track named Audio 1, green for Audio 2) is just for easier visual differentiating; in all sonic aspects, the two channels are identical. Once the files are in track view, they can be slid around the timeline just by grabbing and moving them. We can also trim the files on both the front and back ends in this view, and apply any gain adjustments or envelope shapes (fade-ins and fade-outs).


Fig. 2




The first thing I like to do with files is separate them by the same amount of time. I use three seconds, which is fairly standard, based on the countdown gap used for CDs. Figure 3 shows my markers 3 seconds apart (adjust your timeline to read out min|sec vs. bars|beats), and I slid the two files along their respective track lanes until the end of the first file was three seconds from the start of the first file.


Fig. 3



Note above indications in red. The ovals surround markers, which I’ve named meaningfully (“End Adele File” and “End 3-Second Gap”). The double-headed arrow shows the three-second gap as it looks on the track. But note the descending read arrows on the lower track. You can see that though the “JerryReed” file begins right at the marker, the file contains some silence before the music actually begins. You can fix this two ways: 1) simply slide the track to the left until the waveform aligns with the marker. You’ll have some “region overhang” to the left of the marker named "End 3-Second Gap), but it’s silence, so the listener will still hear exactly a three-second gap between files.


However, the better way is to do what I’ve done in Figure 4, shown by the yellow border, which is to close up the gap in the file itself, otherwise known as “trimming.” This file will be much easier to deal with later on if I take the time now to fix the gap at the file level, and not just its placement in the project.


Fig. 4




Take a look at the way the two files align with the markers below, indicated by the red bracket (Figure 5). Note that I’ve also introduced a fade-out in the upper track, represented by the vertical line and 45-degree line going from top left to bottom right. The vertical line shows the start of the fade, and the slanted line indicates the slope of the fade. Here, it’s a linear fade, but you can have different types of fades, including logarithmic fades, which contain curves.


Fig. 5



Just to be different, in Figure 6 I’m not going to trim the other file’s starting point. This allows me to show off another DAW tool, and that’s the region markers, which are up on the timeline (indicated by a blue downward arrow). The vertical red line shows where the start of the region falls, according to where I’ve dragged the start point to; the arrows show the gap between the beginning of the actual file, as imported, and the first appearance of sound.


Fig. 6



Why would I not want to “do the right thing” and trim the file? Two reasons: 1) there may be a good reason for starting the file in silence, but I don’t know what that is, and I don’t need to know as long as I leave the original files intact and just manipulate the region markers as a temporary fix; and 2) if I’m in a hurry, I can set the region markers and “bounce to disc” (the process of making a separate, mixed-down master file) much faster than I can trim the files plus set the region markers. Sometimes speed is of the essence.



The final step (Figure 7) shows a hybrid of approaches used to prepare a file that was imported into a DAW track. Note the three circles above: the first shows a region marker that aligns with the first appearance of sound, not the beginning of the file; the second show the end of the file, after I’ve crafted a fade-out; the third shows the three-second gap that should follow after every file, starting from where the last sound disappears. This is an important point: If you want a gap between two CD or mp3-player tracks, better to build it at the end of the first file rather than at the beginning of the second file. This way, the operator can lean over and hit the Stop, Repeat Track, or Loop button before the following file plays. When you’re practicing an instrument or running sound effects for a live show, you’ll immediately appreciate this approach. Conversely, all songs should ideally start the moment you hit the play button, unless you have a special situation where you want a gap of silence before the music plays (e.g., you might be practicing along with a piece, and you want to get your hands in place on the instrument after controlling the player).


The arrow at the bottom, bracketed by the two short vertical lines, shows the total length of the region (defined by the markers above), and in the most typical way: a new file where the sound starts immediately (even though the source file has a gap of silence), fades out, and is followed by three seconds of silence before the file stops (or loops back to the beginning) playback.


Fig. 7



1 comment
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dacder  |  September 10, 2014 at 11:30 pm

Great, clear, helpful thoughts!

Many thanks.

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