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 Pro MB.

Unlike Pro Q3, Pro MB is a fully featured multiband compressor/expander with controls for time constants, ratio, knee, and lookahead, as well as the ability to sidechain, upward compress and downward expand. Therefore, Pro MB is ideal for multiband compression/expansion duties, where control over dynamics are most important but over a broader range of frequencies.
For example, you want to compress the upper mid range of a stereo master. In Pro MB you are able to modify the shape of the compression with attack and release parameters. Set the amount of compression after the signal passes the threshold with the ratio. You can set the knee, so that it eases into compression, starting at a low ratio and building to the set ratio when the signal reaches the threshold, this is called soft knee; or instantly compress at the set ratio, as soon as the signal passes the threshold, this is called hard knee.
In addition, you cannot use Pro Q3 as a downward expander to attenuate spill/noise or as an upward compressor to bring up the sustain of an 808. You are unable to sidechain compress the low end of your sub triggered by an external kick drum or modify the degree of stereo unlinking of bands.

Pro Q3 is a parametric EQ with the ability to downward compress or upward expand bell, shelf, and tilt filters. Pro Q3 is much more surgical when it comes to frequency bandwidth and contour, and really shines when you want to downward compress or upward expand a very specific band of frequencies. For example, a bell filter to emphasise the click of a kick drum, or compress resonance with a very narrow Q.
These specific applications are impossible in Pro MB, as you are working within the limits of crossovers and the narrowest band is around half an octave. Crossover slopes are limited to 48dB/oct in Pro MB, Pro Q3 slopes go up to 96db/oct.

In addition, Pro Q3 has a wide range of shelf shapes ranging from analogue, Baxandall, resonant and anything in-between.
Pro Q3 is also great for applications that require both equalisation and dynamic control. For example, your vocal is a little dull, so you boost the high frequencies with a high shelf, the timbre is perfect but there is now some sibilance. Instead of inserting another plug-in in your chain in the form of a de-esser, you can easily add a dynamic band within the shelf to control the sibilance, just set the threshold to compress only when the sibilance is present.

Static EQ - Attenuation

Static EQ bands are desired when you want to boost or attenuate a range of frequencies throughout an entire track or mix.

  • Room Tones - you want to attenuate as much of these frequencies as possible without effecting the instruments timbre. A dynamic EQ would not make sense in this situation because room tones are static throughout the recording.

  • Extraneous Frequencies – if there are frequencies within the track or mix that are not required. For example, the kick drum is pumping nicely but a little too boomy, attenuating this frequency range with a static EQ will eliminate the boomyness whilst retaining the punch. Additionally, if there are excessive sub or lower mid-range build-up throughout the entire track but the dynamic range is balanced, a static EQ dip will be the most appropriate course of action. Utilising a dynamic EQ within these situations would modify the dynamics.

Static EQ – Boosting


Enhancing Frequencies – if you want to enhance frequency ranges throughout an entire track or mix without altering dynamics or groove, a static EQ is best suited,

Dynamic EQ – Downward Compression


  • Excessive Frequencies – these bands are great for attenuating unwanted frequencies that are not constant throughout a track or a mix. For example, a vocal that gets shrill during certain parts of a chorus, a dynamic band can be set to only compress these frequencies when they become excessive. Additionally, when mastering a stereo mix, a dynamic EQ can control a spikey bass or lead note. A static EQ would attenuate this frequency range regardless of if the bass or lead note were playing, thus adversely effecting other elements of the mix.

Dynamic EQ – Upward Expansion

  • Adding Dynamic Energy - upward expansion is great when you want to add dynamic energy to the source. For example, adding click and punch to a kick drum, boosting a static EQ would also brighten the tail of the kick, which sounds unnatural, a dynamic EQ will boost at the transient and then dissipate quickly just like a drummer striking the drum with more velocity.

Dynamic EQ – Downward Compression with Upward or Downward Gain

  • Downward Comp with Upward Gain – You want to boost the low frequencies of your bass but an occasional note is too loud. Lets say a 3dB gain boost works perfectly apart from that note, which is an additional 3dB louder. Here, you would set the threshold to only be triggered by the rogue note and set the range so that the note is compressed by 3dB, thus levelling the bass out.

  • Downward Comp with Downward Gain – lets say you have a synth that has excessive midrange and is a little too dynamic. Compressing the midrange by 6dB sucks the life out of the synth, since it is over-compressed; however, it does sound balanced frequency wise. Compressing the midrange by 3dB provides good dynamic control but does not sound balanced frequency wise. And 6dB of static gain reduction does not control the dynamics. This is a great situation for combining a dynamic band with static gain reduction. For example, you could compress the midrange by 3dB to control the dynamics with an additional 3dB of static gain reduction to balance the frequencies.
    Another example, a stereo-master has too much upper midrange throughout the entire track but in particular during the choruses. Instead of automating a static EQ to attenuate even more during the choruses, you could set a dynamic band with static gain reduction throughout the song but with additional compression during the choruses.

Dynamic EQ – Upward Expansion with Upward or Downward Gain

  • Upward Exp with Downward Gain – you have a kick drum that is too boomy and lacking punch. 3dB of static gain reduction rectifies the boomyness but not the lack of punch. Of course, downward compression would reduce the dynamics further. Therefore, combining static gain reduction with upward expansion is the most appropriate strategy for this application. In this example, I set a dynamic band with 6dB of static gain reduction (3dB more than desired) but with 3dB of upward expansion, this provides the 3dB of gain reduction required to control the boomyness but with 3dB of expansion to add more dynamics.
    Another example, a stereo-master is too bright but a static EQ or dynamic band in downward compression mode loses high frequency energy and sounds dull. You could therefore, use static gain reduction to balance the high frequencies and then add some dynamic life back with upward expansion.

  • Upward Exp with Upward Gain – lets say you have a synth that is lacking in the midrange both in frequency and dynamics. Expanding the midrange by 6dB sounds too dynamic; however, it does sound balanced frequency wise. Expanding the midrange by 3dB provides good dynamic energy but does not sound balanced frequency wise. This is a great situation for combining a dynamic band with static gain boost. For example, you could balance the midrange frequencies with 3dB of static gain boost with an additional 3dB of upward expansion to emphasise the dynamics.

Static and Dynamic Combinations
I believe Pro Q3’s strongest features are the ability to combine both static and dynamic bands.

For example, a high shelf boost with a narrow bell dynamic band. This would be great for the vocal example mentioned earlier, where the high shelf boost produced the desired tone but introduced sibilance. The dynamic band could be set to compress whenever there was sibilance. This is great as it reduces the need for a de-esser later in the chain.

You can also combine dynamic bands together. For example, a wide midrange bell, adding some upward expansion, coupled with a narrow bell, downward compressing a spikey synth note. Or a low frequency shelf, subtly upward expanding the kick and bass, coupled with a bell focused on the kick with more aggressive upward expansion.


Excellent breakdown and analysis @Paul
I own both MB and Q3 and to be honest havent really understood where one would use dynamic EQ over MB.
This is helping me get a better idea of when to use which. Thank you!

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Paul, I haven’t had a chance wrap my head around the new features of Q3 yet so your overview was just perfect for me. Thank you for taking the time to put this together!

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Thanks for the great explanation

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This is Great. I just picked up Pro-Q3. Thanks!!

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Wow! What a great written article. I learned so much. Thank you for sharing.


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Thanks Paul. Your analysis’ and technical rundowns are always educational and helpful. Always appreciated.

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verrry useful intro. Thanks a lot!