Spot Processing Using a DAW

A DAW offers two different ways to apply effects momentarily: plug-in automation and track-adding

by Jon Chappell

The great thing about working with a DAW is that there is often more than one way to get a desired result. Take the example of “spot processing,” which is applying an effect or modification to a single sound, or “sound incident” within a track, rather than to the whole track itself. This comes up all the time in sound design and scoring work, but it can provide a nice point of punctuation in a purely musical context as well. And you can accomplish the task in two principal ways: plug-in automation and adding a special-purpose track. Each has its advantages, which we’ll explore in turn.

Let’s say you want to add a deep reverb, swirly flange, and metallic sound to a final crash cymbal hit. Note that your idea includes the element of reverb, which is an effect you probably have on the track already. A “normal” use of an effect like reverb is usually a set-and-forget proposition. You load a reverb plug-in into a channel’s insert slot, adjust the parameters to taste (including the send and return levels), and you’re pretty much done. It’s very similar to EQ in that you don’t usually make dynamic changes as the track plays.

But you’re not using reverb that way in this case—nor are you likely to use the same type of reverb to produce this dramatic effect. So you have to think about effects—and plug-ins—differently in spot processing than you would for the normal applications.

AUTOMATION TO THE RESCUE

The question is, how do you employ a plug-in that has to come in and out in a very short period of time—perhaps even instantly? The answer is plug-in automation. Most people are familiar with DAW automation for controlling levels: You record your fader moves, and then upon playback the faders move by themselves according to your performance of the previous take. You can also make fader automation moves graphically by drawing envelopes (curves and slopes) in the edit/project window. This too moves the faders accordingly upon playback, but in some circumstances (such as when editing in a really tight spot) it’s better to draw the moves in than it is to perform them.

Automating a plug-in is a very powerful concept. Not only can you bring the levels up and down (on both the send and return controls), but you can automate other aspects as well, including the changing over time of delay time, filter cut-off, EQ, or whatever parameters that particular plug-in offers. It’s exactly the same as volume fader automation, but you may be twisting onscreen rotary controls instead. Some plug-ins, such as Overloud’s Breverb, even offer faders for what would normally be assigned to rotary knobs, to facilitate automation.

Once you realize you can automate your plug-ins, you might think that all you have to do is load in the appropriate plugs for your spot effect, and simply apply tight envelopes for that single passage in the track that requires the dramatic treatment. But there’s another way too.

ADD-A-TRACK STEPS

You can create a separate track to handle just the affected part of the file. On a DAW it’s easy to clone or duplicate a track and place it adjacently to the existing track. Then you have an exact copy of the track, complete with all the mixer settings. But instead of using the entire audio on this cloned track, you’re simply going to use the passage that needs the special processing.

Here are the five steps for employing the add-a-track option for spot processing:

1. Duplicate your existing track and place it somewhere in view of the original (adjacent is recommended, but not necessary). Delete the audio in the cloned track, leaving a track with all the channel settings of the original, just minus the audio content.

Original track selected, at top:

Choose "Duplicate Tracks," copy, etc., as applicable to your DAW.

Duplicated, or cloned track now on top of original:

2. Using the “region split/separate” tool (e.g., Cubase = scissors icon, Pro Tools = Edit/Separate Region) to isolate the desired region for processing. Keep in mind, creating the two edit/split points has no effect on the audio yet; you’re simply providing a graphic edit point.

3. Select the isolated region and copy it. Move the copied region to the cloned track, using the appropriate modifier key to restrict your movements to the vertical axis, so that the clip doesn’t move forward or backward in time.

Selected region, copied into clipboard:

Moved to cloned track, with movement restricted to vertical axis:

4. Once the new clip is in place, you will still have the original region on the original track. You can elect to: 1) mute the original clip; 2) leave it as is; or 3) reduce its gain to give prominence to the new clip. Here, I mute the original using Cubase's Mute function (an "X" in the toolbar).

5. Go to  the cloned track and set up the plug-ins that you’ll use for your special effect (in this case, reverb, flanger, and ring modulator). Adjust the volume fader of the track, as well as any other track controls (pan, EQ, existing plug-in effects) as desired. You can of course automate any of the controls here, too.

THE ADVANTAGES OF ADD-A-TRACK

Many experienced DAW users would employ their automation chops on added plug-ins to the original track, obviating the need for an additional track. But there are several reasons for going with the add-a-track method:

• You now have a whole channel’s worth of control over the spot, instead of just the plug-ins.

• The cloned track requires no automation; set up the track with the special plug-ins, and it will just sit there inert until the spot arrives.

• Having a separate track with a separate clip means you can perform “parallel” operations, experimenting with blending the spot-processed track with the original. You might widen the region boundaries of the copied spot (revealing more audio before and after the copied portion) to effect a smoother blend.

• It’s conceptually easier to add a track with plug-ins than to delve into the automation processes of a particular DAW. This is critical if you work on several DAWs and can’t quite recall each DAW’s particular way of handling plug-in automation. The add-a-track method allows you to start working immediately, which feels better in a “work rhythm” sense, and looks better to a client than if you’re struggling with unfamiliar parameters.

CONCLUSION

Spot processing is just one example of a task that can be handled different ways, and is handled differently by different DAWs. It’s always a good mental exercise to be able to perform the same task in different ways on the same DAW, and over different DAWs. Flexibility is a key advantage in not only DAWs but the person operating the DAW.

\\_\\_

Jon Chappell is a guitarist and the Senior Editor of Harmony Central. He has contributed numerous musical pieces to film and TV, including Northern Exposure, Walker, Texas Ranger, All My Children, and the feature film Bleeding Hearts, directed by actor-dancer Gregory Hines. He is the author of The Recording Guitarist: A Guide for Home and Studio (Hal Leonard), Essential Scales & Modes (Backbeat Books), and Build Your Own PC Recording Studio (McGraw-Hill), and has written six books in the popular Dummies series (Wiley Publishing).