How To Master a Song With Linear Phase EQ
When you’re mastering your mix, the linear phase EQ is the tool for achieving the perfect equilibrium between the highs, mids, and lows in your music.
Today, we’ll discuss why it’s so important, how it works, and when to use it.
What Is Linear Phase EQ?
Linear Phase EQ is the same as any other EQ while still being completely different.
What does that even mean!?!
Well, linear phase EQ is not just another EQ. Think of it as the “maestro’s wand” that’s of higher quality than the EQs we use for mixing. It’s a precision tool that does the same things as any other EQ but with more precision.
Mastering engineers understand that when it comes to EQ, precision is everything. While various types of EQ are available, the linear phase EQ stands out as the go-to choice.
It all boils down to one thing: phase shifts.
Let’s dive into the details.
Why Linear Phase EQ Matters
When you’re mastering, you’re making subtle yet significant changes to the overall piece of music. And if you manipulate the frequency spectrum with a normal EQ, you can introduce phase shifts.
In most EQs, phase shifts are inevitable. They happen when you boost or cut the frequencies in your mix, which causes the sound to “smear.” In contrast, linear phase EQs are designed to eliminate these unwanted phase shifts. The result? A smoother and more precise EQ shift, preserving the integrity of your music.
Think of it like an artist trying to paint intricate details into their painting, but they choose the wrong brush, so the details get smudged. That’s what a normal EQ does. A linear phase EQ does not.
A linear phase EQ is the precision pencil you need to manipulate the frequency spectrum without adding phase shifts into your music.
However, linear phase EQs come with a caveat: they’re notorious CPU hogs.
This means it’s best reserved for mastering rather than applied to your entire mix, as it can introduce latency and affect your track’s timing.
When to Use Linear Phase EQ in Mastering
Mastering EQ is all about the balance between the highs, mids, and the lows.
When you’re mastering, you want to put your linear phase EQ plug-in right there at the beginning of the chain so you can get a nice balanced EQ before you move on to any other processor.
When NOT to Use Linear Phase EQ
DON’T use linear phase EQ in a mixing session.
There may be exceptions to this rule, and of course, there are no absolutes with mixing, but as a general rule, stick to normal EQ plug-ins when you’re mixing.
It will change the track’s timing because it adds a slight delay in processing the signal. This is fine when you’re mastering because you’re only listening to that one 2-track mix. But adding a linear phase EQ to a track in a mixing session will be like adding a really short delay to that track.
So if you added the linear phase EQ plug-in to the drum track, it would sound out of time or like it had a delay effect. So unless you want that vibe on your record, don’t do that.
However, the opposite doesn’t seem to be true because people use non-linear phase EQs all the time on the mix bus and the audio forum trolls largely leave this issue alone.
For instance, my Audio Issues EQ plug-in does not have a linear phase mode, but that hasn’t stopped people from using it on the mix bus, and I’ve received many emails about how much it tightens the low-end and makes the high-end sparkle.
Using Linear Phase EQ – Best Practices
Before we dive into the how-to, remember that subtlety is your ally.
If certain frequency areas are jumping out, you can balance the mix with subtle cuts of 1-2 dBs.
It’s better to add more cuts of fewer dBs (0.5 dB cut at 80 Hz AND 120 Hz, for example) instead of a larger cut across a wider spectrum (a 6 dB cut at 100 Hz, for example).
You must be subtle because you’re EQ’ing the entire mixing session simultaneously. You wouldn’t think twice about cutting 6 dB at 300 Hz to remove boxiness from a kick drum. But if you remove 6 dB at 300 Hz on the master, you’re removing it from every single track in the mixing session, some of which may need that extra mid-range to cut through.
Going overboard may point to underlying mix issues rather than mastering problems, so if you feel the need for bigger boosts or cuts, it might be time to revisit the mix.
Now, let’s break down some common frequency areas for a quick start guide:
1. Taming the Low End
Typically, you won’t need anything below 32 Hertz. Use a musical filter at around 6-12 dB/octave. This helps prevent subsonic frequencies and noise from muddying your mix. Keep the low end clean and clear.
Bonus Tip: Use a mid/side filter that targets the sides. Remove all the low-end below 80 Hz to create a tighter low-end image because the low-end now only lives in the center of the stereo image.
2. Dealing with the Low-Mid Range
If you’re experiencing muddiness in the low-mids, you can target frequencies in the 100-250 Hertz range. Gentle cuts can remove problematic buildup and provide more definition to your mix.
3. Adding Clarity and Presence
You may need to boost frequencies in the 3-6 kHz range to enhance clarity and presence in your track. This can add sparkle and help individual elements stand out.
4. Shaping the High End
The top end of your mix, around 10 kHz and beyond, can be sculpted to bring out the brilliance of your track. A little boost here can add that finishing touch. A boost in the sides in mid/side EQ above 10 kHz will also make the music sound wider.
It’s important to remember that a linear phase EQ is not about drastic changes but refining your sound’s finer details. It’s a mastering tool meant for nuanced adjustments that are supposed to bring out the best of the mix. And if you have a great performance that was recorded and mixed well, subtlety is all you need.
It’s not a one-size-fits-all approach but rather a precision tool that helps you preserve your mix’s integrity and clarity during the mastering stage. So, as you try your hand at mastering your own stuff, keep subtlety and precision in mind. And don’t forget, it’s the little things that make the big difference in your audio.
For more information about the mastering process, take the Master Your Mixes – Make Pro Records course to learn how to make your music sound loud, punchy, and powerful.
If you’re not ready for mastering yet and need help making better mixes in your home studio, check out Step By Step Mixing: How To Create Great Mixes Using Only 5 Plug-ins.
For further reading on related subjects, check out these articles:
- The Only 5 Things to Think About When You’re Mixing
- How to Finish Your Mixes – A Step-By-Step Guide
- How To Use Mastering EQ for More Professional Sounding Songs