“Depth” is one of the two main driving parameters behind most chorus effects, both plugins and pedals. Combined with chorus “rate”, the depth parameter determines how the chorus effect affects your audio. Let’s identify what is the chorus depth feature and where you should set it.
What is Chorus Depth
Chorus as an effect affects the timing and pitch of your audio (see what is chorus). It does this by introducing a low frequency oscillator to directly affect these two parameters, changing them in real time.
Simply creating a duplicate of a track on its own doesn’t make that track sound any different in your mix (aside from making it 6dB louder). This is because that duplicate is perfectly in sync with the original track in terms of timing, and it’s the same frequency from sample to sample.
When the LFO actively changes the timing and pitch of the track it’s applied to, it gives the impression of a unique but similar track based on the nuanced differences relative to the original track.
As I covered in my overview of the chorus rate parameter, the rate determines the speed which the timing and pitch are changing. Measured in Hz of just a few Hz to a fraction of a single Hz (hence the term LOW frequency oscillator), the lower the rate, the slower it makes the transition.
This transition speed is directly affected by the equally important “chorus depth” parameter.
But what about chorus depth?
Measured in milliseconds, chorus depth is the range of the timing and pitch which the rate/speed of the chorus effect is covering.
So if the depth determines how far off the normal timing and pitch the “duplicates” go relative to the original audio, it’s the rate that’s determining how fast it’s happening.
Where to Set Chorus Depth
Setting the depth of your chorus effect will affect the ground covered and ultimately yield very different results depending on how you do it.
Setting it too low will result in less variation, and a more static if not less interesting effect, albeit a more controlled effect.
When we think of that classic kind of chorus sound, it’s generally combining a slower rate with a higher depth.
The net result of this is that we get a slow, evolving kind of sound which covers a lot of ground, the latter courtesy of that higher depth.
Specifically, I like to combine a sub 1Hz rate with a depth of around 4-5ms to create that characteristic “lushness” that also adds a lot of width.
As the timing and pitch go through the range you create with the chorus depth, it goes up and down this range at the chorus rate you have set. Note that with this, you get intermittent overlaps with the original audio, so the width shrinks and expands the more similar or dissimilar it becomes to those parameters of the original waveform.
The more of this effect you blend in either via the Wet/Dry Mix control in the case of an insert or the send dial for the track you’re applying it to in the case of using it as an Aux/Return track, the more of that lushness which will be heard and felt.
If you just want a hint of width without hearing that movement as palpably, simply blend in less via however it’s being applied in your mix.
