Welcome to Sage Audio. Today we’re doing a Saturation Masterclass.
But first, If you have a mix that you need mastered, send it to us
to receive a free mastered sample of it with the link in the description.
Fundamentals of Saturation
This is a topic I’m really excited about, so I’m going to go pretty in-depth about it. The info
from each chapter will build on info from previous ones, so it’s best to watch this one in order.
Saturation occurs when an electrical component, be it a tube, transformer,
or magnetic tape can no longer handle the amount of electricity being fed into it. For example,
with tape saturation, the magnetic particles in the tape have all been reoriented,
but there’s still more signal being input.
This results in both harmonic distortion,
and compression which we’ll cover in more detail in subsequent chapters.
Let’s take a quick listen to some saturation so that we’re familiar with the effect.
Saturation’s Nonlinear Relationships
Saturation causes a nonlinear relationship between the input and output - in other words,
the signal will be compressed, usually gradually or with a soft knee. For example,
if an electrical component has been saturated,
then it’s likely that for every 3dB of additional input, I’ll get 1dB of output.
In this instance, that ratio would be 3:1, just like with a typical compressor. With saturation,
the greater the input after saturation has begun, the higher this ratio.
Let’s listen to how this compression becomes more aggressive, as we push the input’s gain.
If you’re enjoying the video, hit the like button; it helps us bring you more videos
Harmonic Formation and Electrical Components
In addition to compression, saturation results in the signal’s distortion,
which can be observed as harmonics - or generated frequencies related to the fundamental frequency.
Each electrical component will create different harmonic formations, with the
most common harmonics being a 2nd and 3rd order, like with Tube and Tape saturation respectively.
Let’s listen to saturation with a 2nd ordered harmonic,
then a 3rd, to see if we notice a difference.
Do Even or Odd Harmonics Sound Better?
Both even and odd harmonics can improve the sound of your signal;
however, even ordered harmonics have the unique quality
of always being in key with the signal. Since a 2nd order is an exact octave, and higher even
ordered harmonics are higher octaves, the sound’s harmonious with the fundamental.
With odd-ordered harmonics, they may be in key, but they may also be a note
that doesn’t coincide with the notes being played in the song. That isn’t to say they
sound bad though, as odd ordered harmonics can add desirable complexity to a signal.
Let’s again take a listen to even and odd harmonics with this information in mind.
Only a small percentage of people that watch our videos are subscribed, so if
you’re enjoying the video consider subscribing. It’s free and you can always change your mind.
Saturation as Upward and Downward Compression
We talked earlier about how saturation causes downward compression due to the nonlinear
input to output ratio they create - but they also cause upward compression. The harmonics generated
both increase low-level detail and cause a psychoacoustic effect
that makes masked signals easier to perceive.
As a result, harmonics lessen the dynamic range, but from the noise-floor up.
Let’s listen to saturation with both downward and upward compression.
The Frequency Response of Saturation
Just like how various electrical components cause different harmonics and different
compression ratios, they impart unique changes to the frequency response. This
is in part due to the harmonics, since these add signals to various aspects
of the frequency range - but it’s also due to the properties of the component.
For example, slower tape will attenuate high frequencies, while amplifying lows. Although
this aspect isn’t directly caused by saturation, it’ll often be directly tied in with saturation,
since we’re using these components or emulations of them to saturate the signal.
Let’s listen to tape saturation,
with a slower speed and notice the truncated top end and accented lows.
What Makes a Good Analog Emulation?
While we’re on the topic of analog emulation, it may help to know what differentiates a good
analog emulated saturator from a not-so-good one. In short, it comes down to how many nuances of
the original hardware have been accounted for, and how accurate it’s been emulated.
So a good saturator will account for the nonlinear relationship,
as it relates to the incoming frequency and that frequency’s amplitude. It may
also account for mild stereo expansion from crosstalk between an incoming stereo signal.
And as we covered, it should account for the unique harmonic formations that occur as they
relate to the component, incoming frequency, and amplitude, as well as other factors.
Let’s listen to Satin by U-he,
a tape emulation that I think accounts for a lot of the nuances we discussed here.
If you're enjoying the channel, support us by joining with the link in the description
Saturating with a Regular Compressor
If you have an analog emulated compressor that you like,
you can use it for saturation by driving the input while reducing the output.
Additionally, you can introduce your compression as you normally would,
but set the quickest attack and release times possible to add additional harmonic distortion.
If we think of saturation as a combination of compression and harmonic distortion,
then we can use a lot of different plugins to cause saturation.
Let’s take a listen to compression being used as a saturation plugin.
Frequency Specific Saturation
Frequency-specific saturation has been around since the 1970s when the first exciters added
harmonics to the high-frequency range of a signal. Today, we can use a multi-band saturator to affect
different ranges - for example, I could add tube distortion to my lows, and tape to the highs.
The tube distortion will cause some lower harmonics,
while tape will cause a smooth sound and a 3rd order harmonic.
Let’s take a listen to these settings.
Modulated Saturation
Recently, modulated saturation has become an option, in which you can add multiple
envelopes and oscillators to affect how the distortion and compression occurs. For example,
I could create an ADSR filter and attach it to my drive dial to cause saturation
to varying degrees, depending on the incoming signal.
Let’s take a listen to modulated saturation, and notice how it can be used to create
unique saturation that isn’t possible with typical saturators.
If you have a mix that you need mastered, send it to us to receive
a free mastered sample of it with the link in the description. Thank you so much for watching.