Audio Sweetening in Premiere Part 1

In the early stages of editing, especially during the Assembly and Trimming phases, its common to concentrate on the visuals making sure the pacing and continuity of the scene is right.  Once the structure is in place, though its important to make sure that the sound is working at least as well as the picture.

You might not do a full audio mix at this stage but you will want to make sure the sound edits together smoothly and that the various tracks, Dialogue, Sound FX, Foley and Music are balanced and mixed properly.  This stage of the edit is often referred to as Audio Sweetening.

Premiere Pro has all the audio tools needed to do a decent sound mix and you can work on individual clips, whole audio tracks as well as Sub-mixes.

First job is to set up the interface for audio editing.  You can do this by going to the Window -> Workspaces -> Audio menu item.

And then, just to be on the safe side you can reset the layout to organise the windows with      Window -> Workspace -> Reset Current Workspace

The Audio layout is very similar to the default layout but it adds an Audio Mixer panel which you will need for balancing tracks and Sub-mixes later on.  For now we will concentrate on clips in the timeline.

By default, each audio track has a volume overlay displayed on each clip (the white line in the picture  below)

The line shows the volume adjustments for each clip.  You can grab the line and move it up or down to change the volume of each clip separately.  If you hover the mouse over the line, Premiere will show you what the current volume adjustment is:

Sound volume is measured in Decibels, which is written as dB.  A sound playing at its recorded volume, in other words without any volume adjustments, is said to be at 0 dB and as the volume goes below zero, the sound gets quieter.

However Decibels are not a linear scale, in fact every 6 dB drop in volume makes the sound half as loud so -6 dB is half the normal volume -12 dB is half as loud as that ( or 1/4 of the normal volume ) and -18 dB is only 1/8 as loud as the sound was when it was recorded; and a sound at minus Infinity dB is perfectly silent.

Of course we are ignoring the volume setting on the speakers which is a separate issue.

As you drag the volume adjustment line down or up, Premiere will show you how much the volume has changed:

Adjusting each clip one-by-one down the timeline, you can balance the sound through-out the sequence so there aren't any distracting jumps in volume.

This is fine if each clip is recorded evenly without any dips or jumps in volume; but what if the volume of a clip changes, for example if someone turns away from the mic slightly?  It is possible for you to let the volume adjustment change over time buy adding keyframes to the clip.

To add a keyframe, all you have to do is use the Pen tool ( P on the keyboard ).  With the pen selected, you can click on the volume adjustment line to add a keyframe whereever there needs to be a change in volume.  With at least two key frames, you can set the volume at the start and finish of the clip to be different and Premiere will fade between the two levels.  Add the keyframes with the Pen Tool (P) then press V for the Selection Tool and drag down the part of the clip that needs to be quieter.

The default keyframes that Premiere adds cause sudden changes in volume which don't always sound as smooth as they should.  To fix this, you can Right Click on a keyframe and change the Interpolation type to Bezier which will make the keyframe change in a more controllable way:

The Bezier option adds a handle to the keyframe which you can move around to change the bend of the line so the fade-in or fade-out is smoother.

That's it for adjusting clip volume, in Part 2, we'll have a look at adjusting whole tracks with the Audio Mixer.