In this lesson, you will learn how to EQ kick and bass like a pro mixing engineer for that punchy, tight, round, and clean low end.
"If You Are A Mix Engineer, Your Ears Are Your Best Friend.”
~ Udeeksh Sood
How To EQ Kick And Bass In A Mix
EQ Kick and Bass Step-By-Step In A Mix:
- Understand The Low-End Sound Spectrum - Both kick and bass reside in the lower frequency spectrum, that is, below 150 hertz. So we need to understand the lower frequency spectrum before we can begin to EQ kick and bass.
- Understand What Music Needs - Kick and bass play an important role in music. The kick plays a vital role in keeping the pulse, and the bass plays an important role in the groove as well as rhythm. We need to understand this for each song before we EQ.
- Analyse The Kick and Bass Sounds – It is essential to analyse and know the kick and bass sounds. What are their fundamental frequencies; what frequency spectrum should you allocate for kick and which ones for bass; what frequencies are troubling and how do they interact with other elements in the mix are some major questions. All this analysis will help you build a better mix and EQ better.
- Start With Subtractive EQ – Cleaning up the kick and bass sounds, making space, cutting the high end, making it tight and working with sub-bass. All this is done with subtractive EQ.
- Frequency Slotting - Boosting one and reducing other elements to make space and avoid masking issues in the low-end.
- Additive EQ – To boost the tones and add character to sounds, do some additive EQ.
- EQ The Low-End Bus – Working with the bus is what makes kicks and bass glue together and work as a joint force. Make sure you EQ the buses and polish the low end.
- Boost the Upper-Bass Region – This helps in making the bass audible on small-format speakers like laptops, phones etc.
- Use Reference Monitoring and Listen In Mono – Keep an ear on what is happening in mono. Before you are done, listen to what you did on different reference monitors or speakers.
Step 1: Understand The Low-End Sound Spectrum
Frequencies below 150Hz are considered in the low-end frequency spectrum. Even though the human ear is not the best at judging low-end frequencies as compared to mids, the low-end is still most crucial to a mix because low-end relates to feel, groove and pulse for a listener.
Also, as a mix engineer, the low end is crucial for your mix because of the longer wavelength and power. If you sought the low-end in a mix, half the battle is won.
Both kick and bass take up the same frequency spectrum. Most Kicks will have their fundamental frequencies around 50-65 Hz. Most bass sounds will have fundamental frequencies around 40 Hz-100 Hz.
Kick and bass compete for the same frequency spectrum, which makes it challenging for a mix engineer to make them co-exist in a mix. They have ample power which can cause issues like rumble and buzz as well.
Also, both kick and bass take up the centre imaging in a stereo space. This also creates a challenge because you cannot pan one and make space for the other.
So to make space, clean up the sounds and allocate proper frequency spectrum to kick and bass individually in a mix, EQ is a great tool.
Word Of Advice: Before you start with any treatment and EQ, make sure you have set the volume faders of kick and bass properly so that they sound well balanced. If you wish to learn how to set volume levels in a mix, check out this article.
Step 2: Understand What Music Needs
Each song is different and demands you treat it with respect. I could have straight away started this post with Low-cut filtering in an EQ that would not have been wise of me. I want all my readers to understand and treat their sounds as per the needs of their music.
Kick and Bass are present in nearly all songs that you listen to. Kick plays a vital role in keeping the pulse in most scenarios. Bass on the other hand plays a vital role in keeping the groove and feel. But this is not true for all songs. The roles might be inverted in some songs.
All genres have their own set of songwriting layouts, but you will always come across songwriters who do not play by the rules.
So always listen to the music that you are mixing and try to understand what the music demands. What the songwriter’s vision is and how you can better help enhance that vision as a mix engineer.
Understand what type of low-end song structure, songwriter, and genre demands. Is it bass-heavy music like Nu-Disco or kick-heavy music like rock and metal?
You are the best judge, and even before you start any EQing, having a clear vision is a must. Have goals and be clear about what you wish to achieve with EQ.
If you are not sure what your music needs, it is always good to have reference tracks. Listen to similar work and understand the music and how it sounds. Pick up some of the tracks that you think have a similar sound pallet and feel. Also, pick out some tracks that have mixes that are close to what you want your track to sound like.
Word Of Advice: Reference tracks are a great help. I always use reference tracks as guidelines and often cross-reference my work. Reference 2 is a great plugin that all of us should have as mix engineers. I am a big fan of this plugin. With Reference 2 you can quickly compare your mix or master to up to 12 reference tracks and create multiple loops, so you can quickly compare various sections of your track to your reference. A must-have. You can buy it here.
Step 3: Analyse The Kick and Bass Sounds
This might sound rude to some people, but listen and analyse your mix-elements before you follow any advice. No one rule fits all.
Listen to the kick and bass in solo mode for a small interval. Now listen to them together in the mix.
When listening, try to analyse and answer some of the following questions: -
- Which one is deeper and lower in frequency. Is it kick or the bass that is sounding more low-end rich?
- How are they sounding when played together? Is the kick audible with the bass? Is the bass low-end getting pumped when played with the kick?
- Are there any audible phasing issues or nuances in the sounds?
- How are the upper bass and upper harmonics sounding?
- How are the kick and bass behaving with other sounds in the mix, like guitar, synths, vocals, etc?
These are some questions that are often asked before you EQ or do any other processing. Analysing and answering these questions will help you be certain about what Equalisation and other treatments can you do to provide a solution.
Try to understand the fundamental frequency region and harmonics of both kick and bass. Try to figure out the main body of the sound and what frequency spectrum it is in. You can also use a notch and sweep it across the frequencies to help you understand the sounds better.
Once you have a clear vision and goal, it is time to start EQing.
Word Of Advice: If you are facing issues, it is always helpful to use a spectrum analyser. I will be using FabFilter Pro Q3 EQ throughout this lesson. It is by far the best EQ plugin I have used and comes with an inbuilt spectrum analyser as well.
Step 4: Start With Subtractive EQ
Subtractive EQ is the first step, and this is where you should start. In subtractive EQ, you cut out or lower the frequencies that are troublesome or not required in a mix.
Subtractive EQ is done to add clarity and focus and to make space in a mix.
Dealing With The Sub-Bass Region
Start with a high-pass filter on both kick and bass. While cutting out the low end, it is crucial to dedicate either the kick or bass to the sub-bass region. 20Hz–40Hz is considered the sub-bass region. Learn more about the frequency spectrum in this article here.
If you have a separate sub-bass track in your mix, great. Cut out both the kick and bass anywhere till 40Hz with a low-cut. You can use a gentle slope or a steep slope, depending on what you are willing to achieve.
If there is no separate sub-bass channel, it is wise to dedicate the sub-bass region to either kick or bass, depending on how deep they go. If you are working in a genre that is more bass-heavy, dedicate this region to bass and cut out the kick from the same region. If it is a kick-heavy genre, do the opposite.
By doing the low-cut, you are dedicating the sub-bass frequency to one particular element and treating rumble issues as well.
Make sure not to overdo it, otherwise, you will start losing the body of either bass or kick.
Clean it Up
Next, notch out the troublesome frequencies from both the kick and bass. It is better to do this on individual kick and bass channels with separate EQ. Take a bell-curve filter and set it to a high Q value with gain boosted somewhere between 6-9 dB. Now sweep across the frequency spectrum and listen for troublesome frequencies. Anything that is ringing or not sounding good to your ears? Use the notch to lower those frequencies.
Do not overdo notching, otherwise, you will end up with a thin and weak sounding low-end.
Notching out the troublesome frequencies will make the kick and bass sound clean and focused.
It is always good to bypass the EQ to listen for the changes. Also, consider cross-referencing on different reference monitors/speakers to keep your ears fresh.
Consider The High-End Needs
As kick and bass are low-end frequencies, it is wise to allocate them to the low-end frequency spectrum and cut out the high end, making space for other elements in the mix. But before you use a high-cut filter and aggressively cut out the high end, consider the high end of kick and bass and try to understand why it is important for your mix.
If you are working in a genre where you need a hard-hitting kick, you will require the beater sound that is generally in the high-end. Also if you need a bass that cuts through the mix, you will require a high-end. So use your sound analysis done in the previous step and cut out the high end accordingly.
You can use a high-cut filter and a high-shelf filter in conjunction if you do not wish to cut out all the harmonics.
Cutting out the high end makes space for other elements in the mix and also makes the kick and bass sound tight.
Step 5: Frequency Slotting
Frequency slotting is the technique used to make space for either kick or bass near the fundamental frequency region.
Reduce the sound of the element that is less important in a particular frequency and boost the other element.
E.g., If you are working with a kick that is having a fundamental frequency of around 55Hz. Use a bell curve to boost kick around 55Hz by a certain dB and reduce the bass around 55Hz by a certain dB.
This will make space, lower frequency clash and masking issues in the low-end.
Step 6: Additive EQ
Once you get a clean-sounding low-end, time to boost frequencies to add flavour and character.
Additive EQ is an equalisation technique in which frequency regions like body, air, mids etc are boosted.
Suggested Read: Fundamentals Of Equalisation
Boost kick and bass regions that are appropriate to your mix. Here is a kick and bass EQ cheat sheet for your reference.
Frequency Characteristic Kick Bass
Body 45-70Hz 25-100Hz
Punch/Upper Bass 80-250Hz 100-250Hz
Mud 250-500Hz 250-500Hz
Beater/Presence 500-2500hz 500Hz-1.5KHz
Air/Upper Harmonics Above 2500hz Above 1.5kHz
The above cheat sheet is just for reference. Each sound will have its characteristics. Use the above cheat sheet as a guide only to help you in EQ decisions.
Word Of Advice: Be cautious when doing additive EQ as it can easily add phasing issues to the mix. It is easy and more productive to do additive EQ using a separate semi-parametric Equaliser like Black QV2 or Waves SSL G-EQ. Using semi-parametric equalisers makes your workflow fast and reduces the chances of error as well.
Step 7: EQ The Low-End Bus
After all the effort that you have already put in, your low-end should have already started taking shape.
To polish it, take a bus/group for the low-end elements and use an EQ. This bus will help you treat kick and bass as one element and take collective decisions that are good for the mix.
Common practices are to cut out some high frequencies on the bus EQ to make the low-end focused. Also working with a Mid-Side EQ to clean up or boost middle imaging or side imaging is done quite often.
Analyse how the low-end is sounding in the mix and treat accordingly.
Step 8: Boost the Upper-Bass Region
This step is useful especially to make the bass frequencies audible in small format speakers like phones and laptops. Make a bus and send the bass signal to an aux channel. In the aux channel boost the upper bass region parallelly. Using the faders mix the aux signal as per your mix need. This technique is also called Parallel EQ For Small Format Speakers.
Step 9: Use Reference Monitoring and Listen In Mono
Listen for the kick and bass relation in centre imaging and stereo imaging to help you understand how the low-end is relating to the high-end of your mix.
This is a common practice and you should follow it not just for the low end but for your entire mix. Have multiple reference monitors in your mixing room and always refer to your low-end in mono.
This will help you understand how the mix is translating to different speakers and also keep your ears fresh.
Word Of Advice: What EQs Do not Solve, Compressors and Faders Do. If your low end is not glueing together even after EQs or if you are not able to make the kick cut through the bass, consider side-chain compression, parallel compression, multi-band compression and bus compressors. Also, consider using transient shapers to work with sound envelopes and to tame your low-end even more.
This is all there is to EQ, and to shape your low-end. If you have any suggestions or techniques that you use on your mixes, please do comment below. I would love to hear from you.
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