You’ve finished your recording sessions, and now it’s time to process your audio. Get on the fast track to sonic success with Hollin Jones’s essential audio editing tips…
1: Be Mindful of Snap Settings
With audio, as when editing anything in a DAW or a wave editor, keep an eye on whether snapping is switched on and what it is set to. If it’s set to a high value such as bar or ½ you will find precise edits almost impossible to make. On the other hand, if you are trying to cut a whole bar of audio you will want snap-to-bar switched on. As long as your audio is in time, using a snap value will help you make precise edits. A snap value of 1/16 or finer is usually helpful for working with transients inside an audio event. If you turn snapping off you get complete free rein to move events, but it’s also easy to accidentally de-sync your sound by doing this.
2: Zoom In
Software enables you to zoom in on any waveform to sample level, and this gives you a great deal of power. Glitches or other events that last for only a fraction of a second can be identified and processed or corrected by zooming right down. The finer the zoom level the quicker the playhead will disappear offscreen, so it can be a good idea to set up a loop and disable autoscrolling as this will probably drive you mad otherwise.
3: Use Spectrographic Editing
Regular waveforms are fine for seeing the amplitude and duration of audio files, but that’s about it. Spectrographic analysis, on the other hand, can show you multiple visual representations of the frequencies and amplitudes inside a sound based on the type of view that you select. Even better, they provide you with a way to edit sounds in whole new ways. Imagine you have a recording of the perfect vocal take but in the background there’s a car horn that’s crept into the recording – this would be tricky to remove using EQ because the frequencies of both sounds cross over to an extent. A spectrographic editor such as iZotope’s RX or Sony’s SpectraLayers Pro can show you this sound separately and you can then ‘paint’ it out, take a noise print or perform a number of other processes to ‘reach inside’ the sound file.
4: Process in Place
All serious software will let you apply audio processing to files, such as normalization, fades, reverse and usually also plug-ins as well. One interesting trick in some software is to process effects and other tools ‘in place’ on a file. This means opening the audio file in the sample editor, isolating a section of the waveform where you want to apply the processing and then ‘gluing’ it into the file. This doesn’t require you to cut the clip up first, and, for example, is a great way to insert some silence, to perform an EQ cut on one word or sound inside an existing clip, or to reverse a couple of notes from the middle of a guitar take. By processing inside the clip you can avoid cutting it up, though that approach is available to you too, of course.
5: Take Advantage of Compositing
Many DAWs support comping, which is the selection of multiple passes or versions of an audio clip and their combination into one, finished, perfect take. The usual way to achieve this is to record in a loop between the left and right locators, making sure your software is set to keep each take, mute it and record a new version with each pass. Then once you have stopped recording, go into the takes editor (your software will have a name for it) and audition each one. Maybe you’ll find the first line of take one sounded great, then the next line of take three, then the last bit of take one again. By cutting or marking each take appropriately you can build a perfect take from the constituent clips. Mini crossfaders are often available to smooth the transitions between takes.
6: Batch Process Audio Files
This is more applicable to situations where you have already made edits or set up plug-in chains and you want to apply the same settings to a number of files. Loading lots of audio tracks into a DAW, applying a track preset to each one and then exporting them as stems is possible but it’s a long-winded approach. Ideally what you want to do is batch process all your sounds at once. Software such as Sound Forge or WaveLab has built-in batch processing options. With these tools you can make all your settings for a single audio file, say, for example, a plug-in and EQ chain to clean up some voiceover recordings, and then apply it to a bunch of files at once. Hit ‘go’ and leave it to work. It’s a massive timesaver and you can even sometimes specify things such as auto fades at the start and end of each file, further saving you time.
7: Use Time- and Pitch-stretching
Any mid-level or better DAW will support time- and pitch-stretching of audio. They have different names: Flex Time and Pitch in Logic, Hitpoints in Cubase, and so on. Time-stretching is useful to make a clip fit the tempo of your project regardless of its original speed. Spend a little time properly editing its start and end points (since your DAW will work on clip length rather than waveform) and you should be able to snap it to a bar marker to fit it to the project. Alternatively, stretch audio without worrying about snapping to create some special effects, such as extreme slowdowns. Tempo-stretching can be done without affecting pitch, and the reverse is also true. Change the pitch of audio and you can conform it to your project key, duplicate a part to create harmonies and process a clip differently through your mixer.
8:Render Down and Duplicate Parts
When you work on digital audio, edits that you make are generally nondestructive, and that means you can usually go back to any step and undo it. Sometimes, though, certain kinds of edit are only possible on a real audio clip and not on one that’s being effected. Effects are generated in real time and therefore you couldn’t, for example, slice up a delayed clip because the software would analyse the source clip, not the sound of the delays since they were still virtual. The way around this is to simply bounce (not freeze) a copy of an audio part down either by exporting and re-importing it or by printing it to a new track internally. Then, any slice analysis is performed on the effected file, which will look very different to the original. Since you have copies of both you can keep the original too and decide which one to use for what purpose.
9: Use Special FX Plug-ins
You’ll probably be aware of regular plug-ins such as EQ, compressors and reverbs, but there are quite a few effects out there that are capable of much more extreme sound processing. There was a time when to get cut-up effects you basically had to physically cut up all your audio parts and process them through tons of effects. Now it’s much simpler with effects such as Turnado, BreakTweaker or Stutter Edit. These multi-effects simulate complex edits and processing, but instead of taking hours to work on they can be performed with a couple of clicks. You can take fairly ordinary-sounding
10: Extract Groove
Many DAWs will enable you to extract the groove from either a MIDI or an audio part, store this as a quantization preset and then apply this to another part. So you can impose your own groove maps onto recorded or sampled audio parts using this technique to change their feel. Software such as Melodyne and Cubase also lets you extract pitch data to MIDI; so, for example, you can analyse a vocal take and create a MIDI-triggered duplicate.