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FabFilter Pro-MB

FabFilter Pro-MB

5 5 out of 5, based on 1 Review

Multiband dynamics redefined.

18th December 2013

FabFilter Pro-MB by Diogo C

FabFilter Pro-MB


We can all agree that multiband dynamics processors are not the most loved thing in the audio engineering world and they’re especially not-much-loved by the studio professionals. Even though every DAW out there has at least one multiband dynamics tool and processors like the Waves C4 became widely used, their use still stirs controversy among studio professionals – who often sees them as a last resource and more than often one that can only fix. FabFilter wants you to reconsider that, and to convince us all they’re presenting a new way of dealing with the (usually) unwanted phase artifacts associated with multiband dynamic control, and that’s wrapped up with an impressive feature set and a very intuitive user interface. Has Fabfilter conquered the multiband game?

Sound Quality - 10/10

The Pro-MB sounds different than the competition right from the start. Insert it on a track and begin the tweaking process to be instantly rewarded with an unobstructed and very clean sound as you start the tweaking process. There’s no sign of the usual “phasing” and you feel like you have a very precise and controlled processor at your hands, and that’s down to FabFilter’s “dynamic phase” mode introduced in the Pro-MB. This is their weapon to conquer the multiband throne and it’s enabled by default – so the user gets immediately impressed. In order to understand this, we need to take a look at the other two usual multiband implementations: minimum and linear phase.

In minimum phase the signal is splitted through filters and will have phase distortions at the crossover points, and by consequence steeper filters will lead to more noticeable artifacts. The payoff is that there’s no latency introduced and the resources required are very low, so you can have a large number of Pro-MBs inserted before running short on processing power. On the other hand, linear phase mode will split then sum the signal in order to get rid of the phasing artifacts, resulting in a more transparent sound when compared to minimal phase. The downside is an extra dose of latency and the expected pre-ringing induced with linear phase. This is mode is very well suited for mastering and critical mixing applications, where the processing expense is easily justified by the sound quality.

The dynamic phase mode tries to take a page out of each book and cook its own recipe, by only applying its processing when the sound actually suffers a change through compression or expansion. There are no pre-defined filters like in minimum phase, so there are no phase problems at the crossover points and it doesn’t add the pre-ringing or extra latency of the linear phase mode. FabFilter claims that the the Pro-MB uses an “intelligent dynamic filtering” that allows for very few artifacts. This mode can serve basically everything, from the most basic de-essing to complex control, and I’ve found it to be very suitable for critical applications such fine-tuning vocals, mix bus tasks and mastering. The dynamic mode sounds gentler and more subtle from what one might expect from a multiband, and even if you alter significantly the sound of an instrument or a whole song with dramatic settings the Pro-MG holds up very well. Most importantly, it doesn’t sound like you’re dealing with multiple bands – the Pro-MB has a very fluid and natural feel as you go from one frequency region to the other.

However, if that level of refinement is not really your thing, this plugin won’t disappoint you. It can easily become a mangler and that’s mostly due to its substantial feature set. The Pro-MB is extremely flexible and that leads to huge sonic destruction opportunities and it is capable of doing things that will be hard to get elsewhere. There are great tone-shaping options here and if creating new sounds is your goal this is a plugin you should seriously consider.

Complex curves can still sound musical with the Pro-MB’s dynamic phase mode.

Features – 9/10

Flexibility has always been a FabFilter trademark and the Pro-MB is no different: it features basically everything one might expect from a multiband dynamics tool. It does downward and upward compression and expansion. Go extreme on the compression and you have multiband limiting, go extreme on the expansion and you have multiband gate. Pro-MB offers a total of six frequency regions that can be triggered independently, as each frequency region has its own option for internal and external sidechain detection and the regions can be set independently to compression or expansion. The Pro-MB is also one of the few (if not the only) multiband processors that allows the user to tweak the slope of the crossover points, going from a mere 1 db/octave to 40 db/octave super-steep slopes.

One lovely thing is the “expert” tab, which opens up advanced sidechain and stereo manipulation options for each of the region. There's a very clever approach here on the “Stereo Link” slider: from 0-100% it’s a regular stereo link control, but after that it has an extra hundred percent for mid/side operation, with its balance controlled through a little button right below it. The sidechain implementation is no less stunning. For starters you have the usual internal/external options but here’s the first twist: you can have some regions being triggered internally and some being triggered externally and unlike the common approach where crossover points determine what’s getting processed, Pro-MB’s “free” sidechain mode allows you to detach one thing from the other – you can have totally different regions triggering each other.

Needless to mention that all the “classic” dynamic controls are present here: attack, release, ratio, range, threshold and variable knee. Other lovely features includes: global wet/dry, MIDI learn, oversampling, internal bypass, undo/redo, a/b settings and a lovely real-time frequency analyzer with pre/post, pre+post and freeze options. The preset system is also neatly organized and makes storing your own presets a very easy task. FabFilter managed to deliver a nice range of presets covering all the basic compression/expansion/gating operations. One nice touch in the preset department is that the dynamic controls have their own preset menu, allowing you to quick load the desired settings for each region.

Even though this is an impressive feature list, one might miss the inclusion of dry/wet parameter per region and we only have a global control for that. Since all region can operate with independent trigger settings, one has to wonder why FabFilter didn’t implement it. One other thing I miss is a set of controls for tweaking the display, and even though the Pro-MB is very intuitive but its interface looks a little bit faint and could benefit from some color adjustments. Nonetheless, those are small bites as the Pro-MB offers you so much control that this might not even be missed by many users.

Ease of use – 9/10

The comprehensive feature set and intuitive interface makes complex multiband processing seem easy and that might just be the case with Pro-MB once you’re familiar with the basic concepts of such operations. The FabFilter trademark interface is present here once again and it handles things in a very elegant fashion. Upon opening the plugin, you’ll get an empty interface that looks like an analyzer but you’ll notice immediately the buttons to add the bands as you hover the mouse, much like their Pro-Q equalizer. This interface is very intuitive: click to create, drag to move and adjust the frequency regions you want to address. Upon clicking a region the dynamic controls will appear with big dials for the core functions along with some buttons and sliders to take care of the rest. Double-click to enter numerical values. The Pro-MB’s “feel” is very reminiscent of a touch-screen interface.

There’s a lot of visual aid all-around the plugin and one cool thing about that is their tooltip help system. It makes all the relevant information about each parameter readily available – just hover the cursor over the desired control to know all about it. The only issue here is that because of all that information being displayed, this is slightly more graphic-intensive plugin, which is not a problem if you have a half-decent dedicated graphics card since the Pro-MB will take advantage of that. One other issue is that you can get a bit lost on which band you’re dealing with since the separation is not THAT evident and, like I said before, contrast and brightness controls or color customization could be useful. Nonetheless there’s nothing that can blamish the superb work done by FabFilter on the Pro-MB.

Tooltips to enlighten us all!

Documentation and support – 10/10

Fabfilter has a proven track record both in excellent documentation and very responsive and fast support. They also do a great job on providing updates for their products and are always up to speed with the use of new formats – they were earlier adopters of VST3 back in the day and did the same with AAX now. Their documentation is as good as it gets and one thing I love about it is that they don’t use plain text PDF files. Instead, they deliver a custom HTML file with nice indexing, hyperlinks and search function.

Bang for buck – 10/10

At 219 USD MSRP this is quite an easy investment if you often rely on multiband dynamics processors. The Pro-MB might just cover all everything you and if you can’t find what you want here then multiband isn’t really what you’re looking. It is clear that FabFilter tried to please a lot of people with the Pro-MB and they certainly have succeeded. This is a great sounding plugin regardless of the circumstance: the super-picky guys are going to be happy with the inclusion of linear phase and If you’re fine with (or actually enjoy) your regular multiband sound and just want to enjoy the awesome FabFilter workflow, you can choose the minimum phase mode and have the classic sound and artifacts of multiband! If you’re not a fan of either and/or if you like to push for innovation, then the dynamic phase mode is just for you. As some might just want to experiment and get extremely creative on their movements, the Pro-MB is a tool that can provide a vast array of dynamic eccentricities. There’s something for everyone to love here.

For their existing customers Fabfilter offers a nice discount scheme. Your discount is determined by the number of Fabfilter plugins you own. In case you aren’t their customer, you can get a friend or someone here at Gearslutz to send you that coupon so you can join the family, and as a reward that person will get a 14 dollars/10 €uro voucher for each new guy they bring in (the newcomer needs to make a purchase, of course). FabFilter surely knows how to treat their customer and also how attract newcomers!

Score: 9.6/10


Because of its problem-solving and tone-shaping capabilities, the use of multiband dynamics processing is usually more associated with live sound reinforcement and broadcast radio than with critical studio applications. It’s not that rare to find a hi-end studio without any multiband analog processors, and that’s mostly because they’re not as easy to build like a regular compressor or equalizer. That also might explain the lack of “mid-entry” multiband hardware compressors. The great sounding units are very expensive like the ones from Tube Tech, Maselec and also from Weiss, which takes advantage of digital technology and it’s a well regarded piece among professionals but equally costly. Plugins are surely filling that gap and finally delivering great sounding and feature-packed multiband dynamics processors at a very reasonable price.

Attached Thumbnails
FabFilter Pro-MB-tweakinggs.png   FabFilter Pro-MB-tooltipsgs.png  

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