If youâve been following the development of plugin design over the last few years, youâve probably seen a new class of tools making their way into producersâ workflows.
Iâm talking about dynamic resonance suppressors like Smooth Operator Pro.
These unique processors are often lumped in with other advanced frequency and dynamics tools like multiband compression and dynamic EQ.
But how exactly are they different? Can they be used interchangeably? What makes resonance suppression unique and when is it worth using over types of processing?
In this article, Iâll clear up the differences between these advanced mixing tools, point out their pros and cons, and suggest examples for where to use each one in your mix.
Letâs get started.
Fundamentals: EQ and Compression
First off, youâll need to understand the basics of EQ and compression to get started with any of these more advanced styles of processing.
Letâs start with the simplestâEQ.
EQ is your principal tool for managing the tonal balance of the tracks in your mix.
Whether youâre clearing out boomy bass with a high-pass filter or making surgical cuts with a steep notch filter, the underlying action is the same.
All EQs, no matter how sophisticated, are made up of filters that attenuate energy in the signal based on their frequency, shape and characteristics.
Filters can trace their lineage back to the earliest analog processing devices. Think of the equalizer section on a stereo system or mixer. In these devices, the entire signal is routed through the EQ and the components in the filter circuit attenuate the signal more in some areas than others.
Even when you use an analog EQ to boost frequencies, the action often works by cutting in some areas and increasing the level of the remainder of the signal.
For this reason, you can consider EQ to be a fundamentally subtractive process. Digital EQs are slightly more complicated, but they work on the same general principle.
Compression on the other hand, is concerned with dynamics.
Dynamics in music production refers to the changes in volume over time in recorded sound.
Itâs important to control a soundâs dynamic range to make sure the important elements can be heard clearly in the mix at all times.
Compressors help reduce the dynamic range so that all the sounds in the mix can interact in a pleasing way without wild swings in volume.
With those basic concepts out of the way, let's move on to the more advanced versions weâll be talking about in comparison with dynamic resonance suppression.
Multi-band compression
Multi-band compression is like having a separate compressor for each important frequency area in the signal
Recall that regular compressors work by attenuating the signal when its level passes a set threshold.
This works well for most sources, but some sounds youâll encounter while mixing may have varying characteristics across the frequency spectrum.
Multi-band compressors divide the frequency spectrum into distinct areas before applying compression. For each band, the compression only acts on the selected frequency areas.
In the most common configuration, this allows you to set different compression behavior for the highs, lows and middle frequencies.
Multiband compressors rely on steep filters to carve the spectrum into isolated zones. So even though compression is their main method of action, filters still play a role.
Dynamic EQ
Dynamic EQ is a related concept with similar action, but its approach starts on the equalizer side.
Think of a modern digital EQ that supports multiple bands and filter types. For each band that you add, you choose a gain value to determine the amount of cut our boost applied by the filter.
But what if that gain value could respond to the dynamics of the input signal? Thatâs the basic idea of dynamic EQ.
It lets you add dynamic range reduction to each EQ band with its own attack, release and threshold controls.
Like multiband compression, this allows you to process specific areas of the signal to control dynamics. But dynamic EQ is even more surgical since youâre not limited to the typical multiband compressor configuration of three bands separated by steep filters.
Why dynamic resonance suppression is different
So after all that, what makes dynamic resonance suppression unique?
Letâs start with the most fundamental difference. Resonance suppressors are not based on filters, gain reduction or any combination of the two.
Instead they act on the spectral content of the signal by manipulating the harmonic partials that make up the sound.
How do they do this? The key lies in an analysis technique called the Fast Fourier Transform.
Any sound, no matter how complex, can be expressed as the sum of simple sine waves at different frequencies, amplitudes, and phases.
These component pieces are known as harmonic partials, and their arrangement and characteristics determine the timbre of the sound you hear.
The Fast Fourier Transform, or FFT, analyzes the signal to break it down into its individual harmonic partials.
Some of these harmonics sound pleasing and contribute to positive aspects of the sound. But in some cases, frequency energy builds up in areas that give rise to harshness, muddiness or other qualities youâd prefer to reduce in your mix.
These buildups are often referred to as resonances, since you can often pinpoint their distracting harmonics if you listen closely.
Smooth Operator Pro lets you work directly with these harmonics to rebalance their intensity and solve tricky problems that canât be fixed with traditional tools.
What about attack, release and ratio?
If you've already worked with Smooth Operator Pro, youâve likely seen the Comp menu with its familiar attack, release and ratio controls.
While these behave similar to the ones youâd see on a compressor, their action isnât exactly equivalent.
Since Smooth Operator Pro works entirely in the spectral domain, itâs not evening out the level of the signal like a compressor or isolating a range of frequencies like an EQ.
Itâs actually controlling the magnitude of the frequency partials themselves!
This is why Smooth Operator Pro can remove large concentrations of energy without radically altering the tonal balance of the material.
Once you get used to thinking about the dynamics of the spectral components of the signal, youâll get a unique sense of how to work with Smooth Operator Pro.
Fixing problems is just the beginning, and once you get the hang of it youâll find plenty of creative applications for its powerful form of processing.
Where to use dynamic resonance suppression in a mix
So when should you use dynamic resonance suppression, and when are the alternatives a better fit?
At the end of the day, you can use many different types of tools to accomplish your key tasks in mixing. The workflow you choose is ultimately up to you and you may prefer working with one type of processor over the other.
Dynamic resonance suppression, Multiband compression and Dynamic EQ can often be used in place of one another, but they can also compliment each other when used together.
Here are a few situations where you might consider using, one or the other, or a combination of all three.
1. Reduce grating harshness that gives you ear fatigue
Reducing harsh resonances is one of the most popular applications of dynamic resonance suppression.
As I described above, harshness is often the result of accumulations of harmonic energy in sensitive areas of the frequency spectrum.
You may be able to zoom in on harsh frequencies with a narrow band in your multiband compressor, but itâs probably not that areaâs dynamic range thatâs the problem.
Similarly, grabbing a dynamic EQ band in the region will help if you attenuate the signal, but even with the gain cut responding to input dynamics, youâre essentially just cutting that frequency like a traditional EQ!
Speaking of which, regular static EQ is another weapon in your arsenal to reduce harshness. But since the static filter acts on the whole signal, youâll be reducing the intensity of the harmonics, plus whatever else might live in the area where you made the cut.
Dynamic resonance suppression gives you deeper access to just the problematic frequency components. This can often preserve more of the important material in your sound while delivering better results on harsh frequencies.
2. Control dynamics for an entire mix
Complex material like full mixes is where advanced tools like dynamic resonance suppression, multi-band compression and dynamic EQ are most powerful.
A great mix needs to feel balanced and controlled yet punchy and lively with nothing sticking out.
If youâve managed the dynamics well in your individual tracks, you may not need to add any processing to the master bus to get a cohesive sound.
But in many cases, a little additional dynamics control can solidify a songâs groove and glue everything together.
To do it right, you may need to compress each area of the spectrum with its own settings.
Thatâs where multiband compression comes in. You can easily dial in airy open top end, punchy midrange and controlled bass for an entire mix with the standard three band setup.
Dynamic resonance suppression can also be used on a full mix, but itâs much more helpful for bringing back clarity than controlling overall dynamic range.
Try using Smooth Operator Pro on a full mix to gently thin out the density in the lower midrange for additional clarity and a more âhifiâ feel.
3. Reducing aggressive sibilance
Sibilance is one of the most distracting problems that can occur in your vocal sound.
It happens when syllables that contain the âsâ sound pop out in the vocal track after recording.
To reduce it, engineers often turn to de-essers, which are a unique type of multiband compressor.
In a de-esser, the compressorâs action is limited to a narrow band where the âsâ sound is most prominent.
Since the harsh syllables actually do cause the signal level to spike during recording, traditional gain reduction works well enough to attenuate it.
But sometimes you need more. Too much de-essing can result in an uncanny sound that flattens the âsâ syllable into an âfâ, ruining the singerâs delivery.
If youâre at the limit of your de-esserâs power, try running Smooth Operator Pro in series to focus on just the harsh frequencies of the âsâ sounds so your de-esser doesnât have to work as hard.
And If youâre still getting unruly sibilance you can tack on a layer of dynamic EQ for good measure!
Ultimate frequency energy control
In the end, managing the frequency content and dynamics of the sources in your session is a fundamental task in mixing.
No matter which tools you use, youâll have to get a handle on how the key characteristics in your mix influence each other.
With tools like multiband compression, dynamic EQ and now dynamic resonance suppression, there are more powerful ways than ever to artfully blend your tracks together.
Now that you know the basics of all three techniques, get back to your DAW and keep mixing your masterpiece.