# Dynamic EQ vs Multiband Compression



## sndmarks (Jan 11, 2020)

Despite having used both of these types of plugins for several years, I still find them kind of a mystery. It's like they're two different flavors of the same thing - regular vanilla vs French vanilla, if you will.

Can one of you mix/tech guru types help clarify the differences and applications where one might be a superior solution over the other?


----------



## Quasar (Jan 11, 2020)

It's a mystery to me too. There are lots of explanations on the interweb like this:









The Difference Between Dynamic EQs and Multiband Compressors | Black Ghost Audio


Learn how dynamic EQs and multiband compressors work, and how they're different from one another.




www.blackghostaudio.com





That say things like:

_The difference between dynamic EQs and multiband compressors lays buried in their design. Dynamic EQs use their input audio signal as a sidechain source to trigger a parametric EQ that affects signal amplitude. Multiband compressors split their input audio signal using multiple filters, and the signal from each filter is run through its own compressor; these signals are then summed together to create the output signal._

If I had any earthly idea what this means in practical terms I might have an answer for you, but I don't.

Even this article's conclusion is little more than "use whichever one sounds better to you."


----------



## Joël Dollié (Jan 11, 2020)

Hey so the only difference is that a multiband compressor splits the signal with high pass and low pass filters, and then these individual bands work like a normal compressor, so if you solo these bands, it's like if they were individual compressors, controlled by their own individual attack/release, etc.

A dynamic EQ is very similar except that instead of being split by high pass and low pass filters, it's a band that is being automated. The dynamic EQ listens to the band "solo'd" and then reacts based on how loud the signal is, also with attack/release, etc.

Dynamic EQ's can be more transparents, especially when it comes to notching individual resonances. Also technically less phase shift because the signal isn't being split by full on filters.

You can get very similar results.

Multiband compressors tend to have more controls, dynamic EQ's tend to have less but are more convenient to fix small frequency or resonance problems and can sound more transparent due to the ability of having dynamic bell cuts/boosts.


----------



## Dewdman42 (Jan 11, 2020)

That's a nice article! My understanding is that because of the nature of how the DSP is handled in different ways, there are pros and cons in terms of what happens to the sound with both approaches. I can't remember what those pros and cons are, but I've read about them before. Splitting up the signal into bands uses some DSP processing, which will have some kind of artifacts related to that approach....while the dynamic EQ uses a completely different approach in DSP, with different artifacts. How much that matters I don't know.

I think in general it good to use a dynamic EQ for EQ tasks and a multi-band compressor for compression tasks. Yes there is overlap. Figure out which thing you are mostly doing and use the matched tool. I'm probably over simplifying, but this is a complicated topic otherwise. With Dynamic EQ you can eq with a little more flexibility because you able to make the EQ react to the dynamics. So rather then just cutting a certain frequency, you only cut the frequency when it peaks. Conversely with a multi-band compressor, your goal is not to cut a specific frequency range but rather your goal is to compress, its just that you want to compress differently in different frequency bands. While there is a lot of overlap between those two points of view, and prior to the existence of Dynamic EQ, a lot of people solved EQ problems using a multi-band compressor in a creative way for EQing purposes.. but now that we have dynamic EQ's all over the place, its just a lot more simple in terms of workflow to EQ with an EQ...and dynamic EQ just lets you do it a bit more selectively then before. And with compression your task is to compress, but constrain the bands you will compress. I think with either tool you can push them into the zone where they are basically doing the same thing, with differences in the DSP which may or may not matter. But from a simple workflow perspective I hope you get my point about EQing vs compressing and how the tool gets you there.


----------



## Ashermusic (Jan 11, 2020)

I don't really know how it does what it does, but the Punch And Clarity preset on the UAD Precision Multiband makes its way into lots of mixes, always a big help.


----------



## Living Fossil (Jan 11, 2020)

There are overlaps between the two:

E.g. You can (usually) set the thresholds individually in a Multiband compressor.
So you can set realize a scenario where e.g. only one band is effectively compressing.

An interesting tool btw is the Fabfilter Pro-MB: it can work as a dynamic EQ or also as a multiband compressor. In addition, you can also use it as a single band compressor or as a regular EQ.
An in addition you can also use it as an Expander. 
(Dan Worrall't tutorials are quite interesting - also as a general information:


----------



## Dewdman42 (Jan 11, 2020)

Regarding Pro-MB (multi-band compressor), vs Pro-Q3 (dynamic EQ). when to use either one...here is interesting article









Fabfilter Pro Q3 – When to Use Dynamic EQ?


Fabfilter Pro Q3 I thought I would write a quick post demonstrating a few practical applications of dynamic EQ. When should I use Pro Q3 over Pro MB? Like Pro MB, Pro Q3 can dynamically control a range of frequencies. However, Pro Q3 has some advantages and disadvantages when compared to...




mixmasterforum.com


----------



## Quasar (Jan 11, 2020)

Living Fossil said:


> An interesting tool btw is the Fabfilter Pro-MB...



I can't say if it compares to the Fabfilter Pro-MB, and it quite possibly doesn't, but for far less $$$ there is a really cool, flexible tool from Soundspot called Axis. It does a bunch of things, including flexible 4-band (bi-directional) multiband compression and I really like it. I believe it's currently $25 at Plugin Boutique.

I have Fabfilter's Pro-L 2 and Pro-Q 2, but when they wanted to charge me a gazillion dollars for Q 3 _five days_ after the grace period ended, they soured on me. They make great plugs, have cool CP and all of that. And I don't mind that they're pricey, but I do mind that they're pricey and then pricey again for a numeric upgrade. Fuck that.

Axis does what it claims, from my perspective at least does it quite well, and the interface is intuitive and very good, sort of Fabfilter-ish


----------



## germancomponist (Jan 11, 2020)

I have so many tools and at least use only what my ears like the most. You can get best results with all ..... .


----------



## karan212 (Mar 6, 2020)

Dynamic EQs and multiband compressors look similar, have similar controls, and behave similarly. With so many similarities, it can be difficult to identify how they are dissimilar. The difference between dynamic EQs and multiband compressors lays buried in their design. Dynamic EQs use their input audio signal as a sidechain source to trigger a parametric EQ that affects signal amplitude. Multiband compressors split their input audio signal using multiple filters, and the signal from each filter is run through its own compressor; these signals are then summed together to create the output signal.
It seems like a bit of a long and confusing explanation, right? The issue is that if you try to simplify the terminology any more than this, you begin to make statements that aren’t technically accurate.

Ironically, trying to simplify the differences between dynamic EQs and multiband compressors can cause more confusion than clarification. I’ll be walking you through the design concept that powers each type of device, and I'll then provide you with some situations in which you may choose to use one type of device over the other.

Before getting into the nitty-gritty of it all, there's one key difference I'd like to point out between these two devices. A dynamic EQ is capable of reducing and expanding the dynamic range of an audio signal, while a compressor that's acting as a compressor, and not as an expander, is only capable of reducing dynamic range.

Great, so that's the difference? Well, unfortunately, it's not that simple. Many multiband compressors allow you to toggle each band between a compression mode and expansion mode, making the difference between dynamic EQs and multiband compressors just as convoluted as before.


----------



## jcrosby (Mar 7, 2020)

There are some significant differences between Pro-Q3 and Pro-MB. You also have different use cases.

Differences/Pros/Cons:

Pro-MB - Adjustable time constants, ratios, knee settings, lookahead. Bandpass filters limited to six bands with a broader minimum Q. band-specific adjustable sidechain filters.

Pro-Q3 - Non-adjustable time constants, ratios, and knee settings. No adjustable lookahead. bandwidth functions like an EQ, letting you get incredibly surgical with a significantly tighter Q than Pro-MB. No ability to freely assign the frequency response of a bands sidechain filter.

A few examples:

If you're trying to control broad sibilance and you want the dynamics to take advantage of large amounts of lookahead for optimal de-essing - Pro-MB...

- If you have a noisy recording Pro-MB can be used as a multiband noise gate for incredibly clean and transparent noise removal...

- If you want to have control over the behavior of the release - Pro-MB. When managing low end this can make a big difference...

- If you want to sidechain lower frequencies, but don't want the dynamics to behave sluggishly, you probably want to be able to dial in a sidechain filter so that it's triggered by a frequency higher than the band being controlled. (I.e. using the click to trigger a low end sidechain. The sidechain behavior is much snappier and more responsive since it's not reacting to low frequencies which take longer to decay. Really common in EDM.) - Pro-MB...

- If you have a harmonic, or small cluster of harmonics that ring out too strongly - Pro-Q3...

- If you have narrow resonances in different frequency zones, (a vocal booth or poor room for example), Pro-Q3's probably going to give you the most mileage...

Obvioulsy there's overlap, just some ideas of why you _might_ use one over the other.


----------



## Beat Kaufmann (Mar 7, 2020)

*Multiband compressor:*
It acts like a compressor but only in a specific frequency band. So you can compress the bass range of a piece of music and then boost it accordingly. So you get a bass with more "punch" - as we used to say.

*Dynamic EQ:*
Like an EQ, but, it's dynamic. It is controlled (or automatically controlled) by a previously set threshold. Originally, Dynamic EQs were mainly used to attenuate (suppress) signals. Today's Dynamic EQs can also boost when the threshold is reached and more.
Typical applications are, for example, the suppression of frequencies that make a singer's voice sound sharp. Why do you "repair" that dynamically? The dynamic EQ only supresses the sharpness if it is present.

*Attention:*
If too many dynamic effects are used in a mix, the overall result may sound flat and uninteresting. You can avoid this danger by using such frequency dynamic effects very sparingly and purposefully. So a multiband compressor can also be used without the "multi" - i.e. only with one band... 

All the best
Beat


----------



## Ashermusic (Mar 7, 2020)

I have a client who has older tracks done in the ‘90’s that he is bringing me to refresh and make more vibrant. As soon as I put the UAD Precision Multiband on the stereo buss and choose the “Punch and Clarity” preset, it’s halfway there. In all honesty I have not taken the time to analyze what that specific preset is doing but it is the most important tool in my arsenal.

”Real” engineers seem to hate multiband compressors. I don’t know one who has a good word to say about them, but c’est la vie.


----------

