How To Use Mastering EQ for More Professional Sounding Songs

EQ is an incredibly valuable tool to take your mixes to the next level during mastering. Even if you’ve created a spectacular mix, adding a few EQ tweaks here and there to the whole track can often clean up the low end, reduce muddiness and add that professional brightness you thought your mix was lacking.

For instance, one time I was mastering this EP. Although I like to get a second set of ears on the songs and have somebody else do the mastering, in this case, I needed to both mix and master the EP.

I wasn’t approaching the mastering process as a reason to repair anything I had done during mixing. I thought the mixes sounded good enough as they were, but I thought I’d put my mastering hat on and get analytical to make them all sound like a record.

I set the tracks up in the order that I wanted, balanced the levels throughout so they all sounded equally loud, and then I got to work on my processing.

First up was my EQ plug-in. After a few EQ tweaks here and there… a little bit in the lows, a small boost in the highs, and a subtle dip in the mids, I thought things were starting to sound a little bit better.

So I hit the bypass button to hear the difference, and it was night and day!

I was floored. It amazed me at how much cleaner I could make the mixes with just a few simple EQ tweaks, even though my mixes weren’t sounding bad at all, to begin with. These weren’t huge, sweeping boosts or massive EQ tweaks. Just a couple dBs here and there, and because it was mastering, it was all it needed. My mix became more open, had less muddiness, and just sounded cleaner in general.

The EQ made all the difference.

In this post, I’m going to show you exactly how to approach EQ during the mastering stage to get the same results I did in the story above. Mastering is subtle voodoo black magic, not explosive chemistry. Broad but subtle EQ changes are more important than large surgical ones.

So before we get into the frequency spectrum and how it relates to mastering, let me give you a quick checklist to keep in mind when you’re using EQ during mastering.

Your Key Checklist When Using Mastering EQ

First of all, follow these simple steps when preparing your mix for mastering and you should get much better results.

Use Accurate Monitoring

You need to be able to trust your speakers. If you don’t have reference monitors with a reasonably flat frequency response that you know well, your masters will suffer from it.

If your speakers have more high-end than the average stereo system, chances are you won’t add enough high-frequency energy to your masters, making your songs sound dull everywhere except on your studio monitors. And because you can’t exactly invite the entire world over to your studio when you want to show off your mixing and mastering skills, you’ll need to compensate so that your masters translate to every speaker you play them through.

Similarly, if you’re mastering in an untreated room that’s full of standing waves, reflections and flutter echo, you’ll have a hard time hearing what’s coming out of the speakers versus what’s being colored by your room sound.

If you can’t afford high-end monitors or aren’t able to acoustically treat your room, a pair of high-end headphones can help you out in a pinch. If you decide to go that route, make sure you test your masters on every speaker system you come across to make sure they translate well across the board.

Use Metering Tools for Frequency Analysis

Having a frequency analyzer is invaluable when mastering. It allows you to see exactly what the frequency response of a track is and helps you spot any problem areas in the frequency spectrum.

Voxengo Span is my go-to frequency analyzer when I’m mastering. It’s been a lifesaver multiple, helping me spot where my tracks are sounding muddy or when I’m adding too much harshness in the high-end.

If you use Span, make sure you use the Master setting and set the slope to 3 dB/octave to get the most accurate read on the overall frequency balance of your tracks. It doesn’t matter which frequency analyzer you use. Any of the built-in stock analyzers will do the job of helping you create a balanced frequency response in your songs.

Be Subtle With Mastering EQ

Subtlety is key when mastering. A few dB of gain, whether you’re boosting or cutting, should be enough. If you’re more heavy-handed than that, chances are your problem shouldn’t be fixed in mastering and you need to revisit the mix. Remember, you might think four dB isn’t a lot of additional gain, but understand that you’re adding four dB to every single instrument in your mix. Unless you’re comfortable going through your entire mix and adding boosts to every single track at the same frequency, you might want to revisit the mix.

Use Linear Phase EQ

It’s considered “best practices” to use a linear phase EQ when mastering. You’ll have almost zero phase shift so your waveform won’t be abnormally affected, your sound won’t “smear” and you’ll get a smoother EQ shift throughout the frequency spectrum.

However, linear phase EQ is a CPU hog so adding a linear phase EQ on your master bus is a sure-fire way to cause your computer to grind to a halt. Also, linear phase EQ adds a lot more latency so you’ll hear a very audible delay if you happen to add it to an instrument group and not the final mix/master bus.

Also, although the high-end will sound super smooth with a linear phase EQ, the low-end might not fare as well. So if you’re doing a lot of low-end tweaking during mastering, you might want to either revisit the mix, or use M/S EQ to push all the low-end to the center.

Simple M/S Tricks

I don’t always use M/S for the low-end, but it is a great technique to cover your bas(s)es. If you have a mid/side EQ you can use a high-pass filter on the sides and filter out everything below 150 – 200 Hz. That way, all the low-end frequency information is anchored to the center of the mix.

Try it out and see if you can feel the stereo image clean up when the sides of your mix don’t have any low-end boominess. M/S EQ is not just for mastering but can be used throughout your mix for any number of reasons so feel free to experiment with it on vocals, drum groups, and effects.

If you keep these few things in mind when you start mastering, you’ll increase your likelihood of success. Rely on accurate monitoring, use metering tools to help you find frequency problems, be subtle about your EQ tweaks and use the right EQ for each occasion.

Quickstart Guide to Mastering With EQ

Now, let’s talk about some quick EQ tips you can use to create better sounding masters. Remember that mastering is a subtle art. Broad EQ moves are more important than surgical EQ fixes. Narrow filters certainly have their place in mastering, but err on the side of wider to be safe.

Low-End

Filtering – Start with a high-pass filter and set it at 32 Hz. It won’t do much, but it will prevent any subsonic noise from ruining your mix. It may clean up the mix slightly if there’s a lot of sub-bass going on, but speakers don’t reproduce those frequencies that much. However, by cutting those lows, you might be reducing the harmonics and freeing up the higher bass frequencies in general. Also, feel free to add an M/S EQ filter to push the low-end to the center as we previously discussed.

Tonic Note – If the low-end seems fluffy, woofy or lacking in clarity, try to find the root note or tonic of the song to bring out the very low fundamental of the song. That way you’re bringing up the low-end at a particular musical frequency. You’re doing it musically, and it might gel better with the rest of the mix than if you’d just boost the first low frequency you find.

Point of the Kick Drum – Be aware of what you’re losing when you’re cutting the low-end. Even if the mix has a lot of bass, you still need to be subtle when you’re cutting. Take the kick drum for instance. If you cut the lows you might clean up some thickness in general, but you’ll lose the power of the kick drum, and you’ll just hear that clicky sound from the beater. If that’s the case, you might need to revisit the mix or be even more subtle with your low-end cuts.

Low-Mids

Boominess – If your mix is sounding boomy or muddy, you’ll usually find the problem in the low-mids. A wide cut around the 150 – 250 Hz area will often open up a mix that sounds cluttered and heavy in the low-mids. You’ll often hear the mix brighten because you’re subjectively adding more high-mids and high because you’re cutting the low-mid that were getting in the way.

Guitars and Snare – If you need more definition from the snare and guitars, a boost in the mids can often help you out. Start around 500 Hz and sweep slowly around until you get that extra power and definition from those instruments. Be aware that you can’t just get definition in one instrument and not the other when you’re mastering your stereo mix. You usually have to settle for both, or revisit the mix to create additional separation. Whether you think that your snare needs more definition or the guitars need more thickness, they sometimes go hand in hand. Also, that frequency area can make the whole mix sound a little boxy and honky so be careful.

High Mids and Air

Presence – In theory, adding high-mids to everything sounds excellent. That is until everything starts sounding harsh and piercing to your ears. So be careful when you’re adding the 3 – 5 kHz range. Sure it can sound great and bring up the vocal a lot, but it can have the adverse effect of doing too much. Boosts here will often bring out the vocal, which is great when that’s what you need. But sometimes all you end up with is a harsh sounding mix with vocals that are too loud so make sure you strike the correct balance to get an even frequency distribution.

Highs – Nice airy EQ can spice up the dullest of mixes. Nicely balanced highs are often a sign of a professional mix because they sound nice and bright without muddiness or harshness. However, be aware that if you’re boosting all the highs, and you have a particularly loud drum mix you might be boosting the cymbals too much in proportion to the rest. The trick is to find the exact frequency that adds the high-end sheen without washing out the rest of the mix. Often this is higher than you think it is because you’re looking for perceived brightness, not actual harshness.

Brightness – Sometimes your mix is just too bright, but you don’t want to compromise the instruments. If that’s the case, try a high-shelving EQ with a Q of 1 and start it at 20 kHz. Cut a few dB and move it down until you feel you’ve tamed the brightness.

Your Ultimate Guide to Mastering EQ

Take these things into consideration when you’re mastering your track with EQ. Of course, these examples are all hypothetical, and I hope you don’t have to deal with every single one of these problems every time you master them. If that’s the case, you might want to work on your mixing skills for longer. As we’ve said before, mastering is a subtle art, and the EQ should help enhance the great mix you already have instead of trying to fix a song that’s poorly mixed.

If you already have an excellent-sounding mix that just needs a little mastering EQ across the board, using the EQ tricks above should help you start making your home studio mixes sound like professional masters.

For even more in-depth information and training on how to use EQ to create separation and balance in your mixes, so that you can create professional mixes you can be proud of, check out EQ Strategies – Your Ultimate Guide to EQ here.

You can get this entire Mastering EQ guide as a free PDF that’s included with the course so hit the link above to check it out.

If you liked this post, share the love: