How To Clean Up A Muddy Mix

Like most engineers, I’m sure you’ve dealt with mixes that sound like a bunch of tracks pig-piled on top of each other and are fighting for room to breathe in the pile. Even those who took the time and care to clean some of this up during tracking will need to do a bit of work to pull everything apart. The tracks we start mixing will be inherently messy if they haven’t had some clean up or editing done prior to the session.

This muddiness is completely fine and expected when you’ve got enough experience dealing with it. A good mix engineer should be able to acknowledge the mud, develop a strategy to clean it up, and will continue to clean and polish it until they’ve got a solid, mud-free end result.

Here are some of the biggest places you can make headway against a particularly muddy session:

Percussion First

Although the majority of percussion focuses around terms like “snap” and “body”, another common way to describe them can be “boomy”. A boomy bass drum isn’t always a good thing; it can mean excess resonance within the shell. The same can happen for the rest of your drum kit too – unwanted ring in your toms and snare.

To clean this up, engineers have a few tools at their disposal. EQs can work well to roll off some of the low-end build up that occurs. Compressors can tighten up individual drums of the entire kit as a whole.

If your issue is less with the mud in a particular shell and more to do with the bleed from the shells around it, you may be better off with a bit of automated filtering. If you’re new to the concept, it essentially requires rolling off the unwanted noise after a drum hit. You can automate the frequency for a much more natural sound than a gate can provide. This filter-based concept was the driving force behind Tominator, which has saved me a ton of time I used to spend manually automating the bleed out of my toms.

Bring In The Mix

Once you’ve got your drums cleaned up, spot treatment in other instruments and microphones might still be required. Start with your drums soloed and bring in the rest of your mix one piece at a time, listening for other tracks that start to add muddiness when they enter.

If you have a preconception of where your problem might lie, start with those tracks first. Instruments that are traditionally bass-heavy are usually my go-to – things like bass guitars, samples & synths. Acoustic instruments can also be particularly muddy since they experience the same types of resonance your drum shells do.

Moving up the ladder to mid-range instruments, you’ll want to seek out those that occupy the same part of the frequency spectrum. Keep an EQ handy and don’t be afraid to pan them out a bit if necessary to create space. Two or more instruments trying to occupy the same space, like a vocal and lead guitar, often cause mid-range muddiness. By cutting a few dB notches where each instrument predominantly sits, you can make room for both without losing sonic integrity.

If you’re having trouble finding problem frequencies a spectrum analyzer can help target them. Just use it as a loose guide – at the end of the day it should be your ears, not eyes, which make your mix decisions.

Cleaning Up Your Master Fader

Once your tracks have been cleansed of muddiness, there’s only one place left for you to treat before they hit your speakers. Your master fader is where a lot of your signature sound comes from as a mix engineer. While some prefer to leave this section completely clean, it’s a great place to develop a signal chain as a sort of stamp of approval before your music gets printed down.

What goes into this final chain is up to you, but I will add a few words of caution: treat your master bus gently or risk completely ruining your mix.

A stereo EQ on the master bus can give you a quick fix for remaining mud, but it should be used sparingly and only in situations where you couldn’t fix it earlier in the mix at a track level. Before you start down this path, I highly recommend reviewing our Beginner’s Guide to Multi-Brand Processing.

After that, some bus compression is always a nice touch to tighten anything up at the end of the chain. Tools like BG-Mix were designed for the master bus, and can be pushed a little harder than I’d recommend for a standard compressor. By adding a compressor at the end, all of your small tweaks to make space in your song will be melded together into a tight, professional mix.

Practice & Patience

Muddy mixes are common and require both practice and patience to address correctly, but cleaning these sessions up are a key part of what makes us audio engineers. Develop your own process for dealing with these issues head-on and soon enough you’ll be able to get back to the creative part of the mix process we all love.

Want to see how others are addressing muddiness issues? Come join the discussion in the Joey Sturgis Tones Forum on Facebook.