EQ Techniques You Need To Be Using

By Donald Dinsmore

No tool is more important than EQ when making a mix.  EQs allow you to carve volume away from select frequencies of a sound in order to make room for the other sounds in your song.  Having a clean mix means that every element in your track has its own place and can be distinguished from the other elements in the song.  Of course there are other mixing tools producers use to achieve clean mixes but every sound is comprised of frequencies and if you can get those straight your mixes will really shine.  Try applying these EQ tools to take your mix to the next level.

Mix Harmonically

When you make cuts remove frequencies that are not in key with your song.  For example, let's say the key of your song is E minor, if your snare and pad are fighting for space you may try tuning your snare to a note from the E minor scale, say G (200Hz).  Instead of making a cut in your pad at 200Hz, cut at a note outside of the E minor scale like G# (208Hz).  This way you will be removing frequencies that are causing deconstructive interference and allowing the in key frequencies to harmonize with other notes in the scale. 

High Pass Return Tracks 

Do you use reverb and/or delay as a return effects?  Make sure you high pass the output of the reverb or delay on your return tracks around 250Hz to eliminate low end rumble and unwanted stereo width in the low end.

Avoid Massive Cuts and Boosts

Massive cuts often result in a weak, paper thin sounding tracks.  Massive boosts sound unnatural and can introduce undesirable resonance to your tracks.  

Cut Narrow, Boost Wide

Narrow EQ cuts are more transparent than broad cuts.  Boost with a wide Q, narrow boosts result in audible resonances.

Pole 2 has a high Q making the cut narrow.  Pole 3 has a low Q making the boost broad.

Pole 2 has a high Q making the cut narrow.  Pole 3 has a low Q making the boost broad.

Evaluate EQ Changes In Context

It really doesn't matter how  the sounds in your track sound on their own.  The reason being, most of the sounds in your track play at the same time other sounds.  Decide if the EQ changes you made sound good while you listen to the whole song.  Ask yourself, "Do these EQ changes make my song sound better?" instead of, "Do these EQ changes make my [insert instrument here] track sound better?"

EQ Changes The Gain

That's right, changes to your EQ affects the volume of the track you're EQing.  You're probably thinking, "Well Donald of course EQ changes the volume," but it took a long time for this idea to sink in and I figure this is probably news to some of you.  EQ cuts reduce the volume across the band dictated by the Q of the EQ pole.  EQ boosts raise the volume across the band dictated by the Q of the EQ pole.  This is one of the reasons the old axiom, "It's better to cut than boost" holds true.  Things that are louder are more satisfying to our ears.  If you boost with EQ your brain may be tricked into thinking it sounds better when it really only sounds louder.

High Pass Everything

Apply a high pass filter to every track in your song even if you think it doesn't have frequency content in the low end.  It can be astonishing how much low end can be part of a hi hat.  That low end rumble and room noise eats of headroom and makes it hard for your bass elements like the kick and sub to cut through the mix.  My strategy is to set pole one of EQ8 to high pass mode and sweep it up.  I continue sweeping it up until I can hear the EQ, then I bring it back a little bit so the effect is not audible.

See what I'm saying?  This is a hi hat.  Check out all of those low frequencies.

See what I'm saying?  This is a hi hat.  Check out all of those low frequencies.

Don't EQ Unless You Need To

Have you ever grabbed an EQ preset, slapped it on a track and then moved onto something else?  I'll bet you have and I challenge you to tell me why.  Sometimes a track doesn't need EQ so save yourself the CPU usage and ditch the EQ.

Seek and Destroy Resonant Peaks

Is there a sound in your track that you find highly irritating?  Sometimes this is caused by a resonant peak.  Even if you have well trained ears they can be tricky to hone in on.  Try making a narrow EQ boost (to add more resonance) and sweep it across the frequency spectrum.  When you sweep over the resonant peak you will hear a loud whistling sound (make sure your monitor are at low volume).  Make a narrow cut at the frequency you hear the whistling.  Note, you will hear a lot of whistling as you hit harmonics through out the spectrum, the place to cut should be extra loud.

Sweep the narrow boost from low to high frequency across the spectrum.

Sweep the narrow boost from low to high frequency across the spectrum.

A/B Everything

How do you know you're EQ moving and shaking sounds better?  You don't unless you compare it to the unprocessed sound.  Bypass the entire EQ and/or individual poles.  Mixing is the stage of your workflow where you need to be critical.  So be critical!

Listen In Different Spaces

Room acoustics plays a huge part in how we make mix decisions and decide what sounds good or not.  You may be inadvertently biasing yourself to systematic mix errors if you only listen to your mix on one set of monitors in one room.  Listen on headphones, listen on laptop speakers, listen in the living room, listen in the car on the way to your friend's house, listen at your friend's house etc... You may be surprised by the differences you hear in your tunes.  

Use EQ To Tighten Low End

Did you know several EQs have Mid/Side mode?  Applying a high pass filter on the side channel will remove stereo information in the low end.  A good rule of thumb is to have your mix mono (only Mid) below 200-300Hz so set the cutoff frequency of your high pass filter around there.

First you need to change the mode using the dropdown menu on the left side of EQ8.

First you need to change the mode using the dropdown menu on the left side of EQ8.

Click on the Edit button to change from M (Mid) to S (Side).  Apply a high pass filter and you're good to go.

Click on the Edit button to change from M (Mid) to S (Side).  Apply a high pass filter and you're good to go.

Add Stereo Width With EQ

Stereo width is the result of differences between your left and right channel.  Here's how you can use Left/Right mode to add Stereo width to you tracks: 

Cut the Mud

Mud is a frequency build up in the 200-400Hz range of your track.  The reason these frequencies are a problem is because they are in almost every element of your track.  Make shallow, narrow cuts in this range on some (or all) of the tracks that contain these frequencies.

Make Room for Vocals

Frequencies between 2-4kHz are essential to the presence of vocals in your mix.  Instead of boosting these frequencies try making narrow cuts on other tracks to make room for the vocals.  This range may move around a bit depending on the key of the song and the vocalist. 

Low Pass That

Use low pass filters to save headroom.  Unless you're making music for dogs your song won't benefit from frequencies exceeding 20kHz.  Apply low pass filters your tracks at around 20kHz using EQ.  On some tracks you may be able to cut lower.  Don't get carried away!  Your music may begin to sound dull and lifeless if you remove too much of that 10-20kHz range.  

Check out the Spectrum of MiHKAL's Hornography.  Notice the absence of frequencies exceeding 20kHz?

Check out the Spectrum of MiHKAL's Hornography.  Notice the absence of frequencies exceeding 20kHz?

Beware Nyquist

If you're making EQ moves in the high register consider using EQ8 in Oversampling mode.  Right click on the title bar and select Oversampling from the dropdown menu.  Oversampling mode exists because aliasing can occur at one half the sample rate, called the Nyquist Limit.  For example, if the sample rate you're using is 44,100 samples/sec (CD quality), the Nyquist Limit is at one half of the sample rate, therefore 22,050Hz.  Therefore, if you are EQing frequencies at or above the Nyquist limit you may hear aliasing.  To solve the problem use Oversampling mode. 

It's Just A Phase

EQing alters the phase relationship of an audio signal.  This little miracle of physics can result in phasing issues, especially if you're layering sounds together. The steeper the EQ cut or boost you apply to a signal the greater the phase shift.  If a phase change is causing mix problems try making a less steep EQ curve or using a linear-phase EQ like Fabfilter Pro-Q.  

Not All Is Equal

Different EQs sound different.  Some are transparent and ideal for sonic surgery.  Other colour the signal.  Try using different EQs for different jobs.  EQs like Ableton's EQ8 and Fabfilter Pro-Q are very transparent while Softtube's Abbey Road Brilliance Pack EQs add warmth and depth to the signal.

Less is More 

If you find yourself making major EQ adjustments (+/- 3dB or more) to your master, just don't.  Go back to your mix and fix the problem there.

If you made it this far you probably know more about EQs than you did before.  But before I wrap this post up I want to leave with one final thought.  Try to imagine your song occupying a box.  The box has three dimensions of sounds separation.  Front to back is volume, left to right is panning and stereo width, while top to bottom is frequency.  Your goal when making a mix down is to give every sound in your song it's own unique place.  Best place to start is gain staging and deciding what sounds you want at the front of the room closer to the listener and what sounds you want further back and quieter.  Next, separate the elements of your song in terms of frequency.  EQ and song arrangement achieve this separation.  At the bottom of the room you might have your sub bass, above that your kick, followed by snare and vocals, all the way up to the hi hats.  The last step is to spread elements out using stereo effects and panning.  By learning and applying the EQ tools discussed in this article you will be a whole lot closer to that crystal clear, professional sounding mix.  Go forth, be inspired and make music!

Stay in the know!  Sign up for our newsletter to receive more music production and DJ tips and tricks, and special offers.