Mixing low end is a bit of a nuanced art, demanding both precision and some creativity. Achieving a clear and balanced low end can be the difference between a professional and your average, amateur mix. So no matter your current level of experience, understanding these tools and methods is crucial for a well-defined and impactful low end.

With these tools and techniques, you can master the art of mixing those elusive bass frequencies to perfection. Join Noize London as we explore four game-changing tips focusing on the capabilities of the FabFilter Pro MB and how to effectively use sidechain compression.

Let’s begin!

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Mixing the Low End with the Pro MB

First we’re going to focus on mixing the low end with the FabFilter Pro MB and sidechain compression with a track submitted by Boombox user Cameron Thias.

Before we do any sidechaining, we needed to create a 4-to-the-floor ghost kick drum because of the extra kick—the additional rhythm—in the original. We’ve duplicated and looped this new ghost kick and then muted it so that it just acts as a signal. We don’t want it to add volume or layer the original kick.

First we’ll feed that ghost kick audio signal into FabFilter and create a really large band–as shown in the video. At the bottom, go to Expert and make sure that you’re feeding in the external signal, make a fast Attack, the Release at just under 20%, increase the ratio all the way up, and also turn the Lookahead to 20 ms.

We’re also going to bring the range all the way down. Now we just have to adjust the Threshold to determine how much of the kick we want to affect this compressor so that it ducks in volume each time the kick is playing.

In our example, the FabFilter is reacting to the entire kick signal, that is, from 20 Hz to 20,000 Hz. But what if we wanted the compressor to react only to the “clicky” part of the signal to make a sharper and more accurate sidechain?

We’ll go over to Free, and you’ll notice a movable band. This is the band of frequencies that it’s letting into the compressor from the kick. We’ll un-solo the kick and click on Audition. When we enable Free, we can then decide which frequencies the compressor reacts to from the sidechain kick signal. With a tighter sound it gives us more control because the click is shorter and tighter than the low end. So if you want more pump, or something tighter and more surgical, this gives you a lot more advanced options.

fabfilter pro mb sidechange with the bass

Sculpting Your Bass & Kick

The next track we’ll look at was submitted by Boombox user Stoif.

We’ll start with a listen to the kick and bass. And with this track, we don’t really need the entire bass pumping. We just need the low end of the bass to duck every time the kick plays because the mids and highs are already providing some nice distorted information.

No need for a ghost kick this time, so we’re just going to feed the original kick into the sidechain input and do a low shelf. Then we’ll go to Expert, switch to External so that it’s feeding in the sidechain signal. We’ll leave the Ratio where it is, set a fast Attack, Ratio and Lookahead all the way up, and bring the Range way down to about -18 dB.

Next, we’ll decrease the Threshold until we reach the desired amount of compression. Here we can get the low frequencies to duck out of the way, leaving our mids and highs intact. This can be a great approach to keeping your mix nice and balanced.
But as in our last example, it’s reacting a little too heavily to the low frequencies of the kick, so it’s not nearly as tight as we’d like it to be. So we’ll select Free to control which kick frequencies are entering the compressor, then Audition, and then we’ll play around with it a bit.

We can also adjust the release depending on how much of that pump you’re looking for. Short and tight, or long and smooth? Up to you. With our adjustments we have much more space for the low end while still keeping the sound natural.

fabfilter pro mb sidechain

Bringing out the Kick

For our next track, we have a bonus tip!

We used the FabFilter to control some of the high frequencies—there’s no sidechain happening here. This is directly on and reacting to the sole signal. The hats needed some taming, and the kicks just feel too dynamic. In fact, the kick drum is barely audible at points.

We wanted the FabFilter Pro MB to help bring those kicks out of the mix. We started by creating a point around 120. By a two-finger stroke on the track pad you can increase and decrease the slopes to 48 dB, making it nice and sharp and thin as possible.
We’re then going to Solo it and move it around to find out where our kick sounds the most dominant. And instead of compressing downwards, we’re going to expand. This means that when the kick’s signal crosses the threshold—rather than being pushed down in volume—it’s actually increased.

Next we’ll select Expand, increase the Range so that it’s going in the opposite way, fast Attack, fast Release, and then we’ll make the Knee hard so that the signal affects the compressor in a more immediate and aggressive way. So now the kick is more audible, but it’s not yet balanced with the sub and bass.

fabfilter pro mb

Multiband Compression with the FabFilter Pro MB

Next we’ll tackle some extreme multiband compression without a sidechain to bring them both up, add more sustain, and help it feel warmer to match the rest of the track.

First we’ll do a low cut in FabFilter, and make the Range big, around -26 dB. Leave the Attack and Release where they are for now, and then just adjust the Threshold so that we’re overdoing the compression a bit. And by adjusting the Output we’re increasing the volume of the frequency area that we’re compressing.

By increasing or decreasing the Attack, we can decide how punchy we want it. For this example, a medium Attack appears to be the most natural, so we’ll stick with that. Always remember to listen in context with the whole track though.