Often unnoticed and unheard, sub-bass is the deep and powerful foundation of countless genres, from rock to hip-hop to pop and beyond. The frequencies range from a near-subliminal 20 Hz to a more perceptible 60 Hz , while standard bass often lies between 60 Hz to 250 Hz and is more ear-catching.

Knowing how to use sub-bass in a mix is essential if you want to live up to modern production standards, and knowing how to manipulate these frequencies, whether in a hard-hitting hip-hop track or a rumbling, cinematic underscore, is part of understanding how to transform a good track into a great one.

In this guide, we'll explore all there is to know about these ultra-low frequencies, including practical mixing tips and how to creatively use them to make sure your tracks have the perfect amount of depth and body.

What Is Sub-Bass?

Sub-bass occupies the lowest range on the audible frequency spectrum (humans can hear between 20Hz and 20kHz) between 20 Hz to 60 Hz. Though the range is barely audible, offering more of a sensation of sound rather than the sound itself, it's what you feel vibrating through your body at a live concert or in a club.

The sub-bass serves several functions in music:

• Foundation : It provides the underlying anchor for a track, whether the low frequencies in a kick drum, bass, or synth.
• Emotional Impact : Sub-bass frequencies are deep, powerful, and intense, giving us the rumbling sensation we feel in our bodies when listening to music.
• Depth and Fullness : It fills out the lower end of the sonic spectrum, giving the music a richer, fuller sound that can be felt physically by the listener.

While some people use "bass" and "sub-bass" interchangeably, as they both refer to lower frequency ranges, they differ significantly in their placement within the frequency spectrum and their impact on music.

Standard bass frequencies, ranging from 60 Hz to 250 Hz, are typically more audible to our human hearing. This is because as we move further up the mid-range, frequencies become more prominent.

Sub-bass, on the other hand, is felt more than it is heard, providing the physical sensation that concert-goers know all too well.

Picking the Right Key for Sub-Bass

While sub-bass can refer to the frequency range in which ultra-low frequencies live, it can also refer to a type of sound or instrument used in music production.

When you incorporate sub-bass in your mixes, selecting the right key is crucial .

In the sub-bass range, you'll find a variety of notes, though not all are equally suitable for every system or listening environment.

If I'm starting off a track that I know will showcase the sub bass quite a bit, I like to work in keys between F and A . The notes between F0 (approximately 21.83 Hz) and A0 (around 27.50 Hz) are generally considered the best choices for sub-bass frequencies, as they're low enough to provide the physical vibration that sub-bass is known for, yet high enough to be within the reproduction capabilities of most good-quality subwoofers and sound systems.

While you can certainly go lower in the frequency spectrum, reaching down to notes like C0 (approximately 16.35 Hz) through E0 (approximately 20.60 Hz), not all subwoofers are capable of accurately reproducing frequencies this low. As a result, listeners might not be able to experience these low frequencies like you intend.

Choosing the Right Style of Sub Bass

If you're incorporating sub-bass in your tracks, you have a few options.

Sine Wave Sub Bass

Perhaps the purest and most fundamental form of sub-bass, we have the sine sub. A sine wave is a representation of a single frequency without any harmonics, perfect for when you need to generate a smooth and clean tone.

Its simplicity is what makes it extremely versatile, perfect for adding depth without cluttering a mix. I often find myself using a sine sub-bass when I need absolute clarity and subtlety, such as in ambient or R&B mixes. With a lack of harmonic content, you don't have to worry about it competing with other elements in your track.

Square Wave Sub-Bass

If you want to introduce a bit more harmonic content into your mixes compared to sine waves, you can use a square wave sub (or simply saturate your sine sub to add harmonics). I love a nice saturated sub for more aggressive genres, such as dubstep and drum and bass.

By adding harmonics, it's easier to hear the sub-bass cut through, especially in denser mixes.

808s

808s have become a staple in hip-hop, trap, and electronic music, which is why I feel like they deserve a spot on this list.

Your typical 808 is derived from a sine wave and manipulated with different parameters and effects, such as altered decay envelopes, pitch drops, and saturation.

When you want your sub-bass to play a lead role in your track or provide a focal point for melodic content, 808s are incredibly effective.

How to Layer Sub Bass

In many instances, I find myself layering sub-bass underneath other bass sounds to give them a deeper, more palpable feel.

Of course, if you've ever tried layering sub bass sounds underneath something like a bass guitar and ended up with a muddy mess, you know it's not as easy as it sounds. There are few techniques to keep in mind for layering sub-bass sounds effectively:

• Choose Complementary Tones: Selecting a sub-bass sound that complements your main bass rather than competing with it is key. Typically, when layering, a sub-bass should be a simple, clean tone like a sine wave, so that you can fill out the low end without intruding into the clarity of the bass.
• Adjust Your Octaves : Try writing out your sub-bass and bass in different but adjacent octaves. Ideally, your sub-bass frequencies should sit at least an octave below the frequencies of your main bass to mitigate phasing issues.
• Fine-Tune Your EQ : Once they're layered, you can use an EQ to carve out specific frequencies within your bass and sub-bass layers so that each has its place in the mix. For example, I like to apply a high-pass filter to my main bass to clear out the lowest frequencies and create space for the sub to sit neatly underneath.
• Control Dynamics with Compression : If your bass is too dynamic, your mix will feel all over the place. Ensuring the volume is consistent throughout means using compression to maintain a consistent level between the bass and sub-bass.
• Use Side-Chain Compression : If your sub-bass is starting to swallow up other low-end instruments in your mix, such as your kick, consider using side-chain compression. By compressing the sub-bass slightly when the kick hits, you can keep them out of each others way, creating more headroom in your mix while clearing up real estate in the low frequency range.

If you can't hear sub-bass on your system, whether it's because you're listening on smaller speakers or headphones that don't reproduce the bass frequency spectrum very well, it's often advised to use a bit of saturation to give your sub harmonics. As an added benefit, doing so will make it more perceptible for other listeners with low-end, consumer-grade listening systems.

Top VSTs for Sub-Bass

While just about any synth VST will offer the tools you need to create a decent sub-bass, there are some that have become go-to tools for me, especially when I want to shape the sub frequencies to my liking.

Massive X by Native Instruments

Massive X was introduced not to long ago after years of its legendary predecessor, Native Instruments Massive, ruling the market for electronic music producers.

With a powerful new oscillator section and advanced modulation options, it's one of the most in-depth tools for crafting precise and deep sub-bass. If you've used Massive in the past, you'll be happy to know that there's tons of new filters, effects, and sequencing capabilities in Massive X.

Rob Papen SubBoomBass

Rob Papen’s SubBoomBass is another one of my favorites for creating deep, powerful sub-bass tones. While the interface might look a bit overwhelming and more like a synthesizer than a sub generator, it was purposefully designed to create impactful subs for genres like hip-hop and EDM. There are plenty of presets to use as jumping-off points and several unique tools, like the sequencer and groove control modules, which you can use to pump out rhythmic bass lines.

Xfer Records Serum

Serum by Xfer Records might be one of the most popular synth VSTs on the market today, and with its versatile wavetable synthesis engine, you get unparalleled control over the way in which you can shape your sub and synth sounds. My favorite feature has to be the real-time wavetable manipulation, especially when it comes to in-depth sound design.

Future Audio Workshop Sublab

SubLab is specifically tailored for sub-bass and 808-style bass production, combining synthesis, sampling, and effects in one compact and focused package. Whenever I need an 808, this is where I go. The interface is gorgeous, the sounds and samples are versatile, and there are endless effects and parameter options for getting punchy, distorted subs and 808s.

HexLoops X-Sub (Free)

Don't have the cash to spend on other instruments?

No worries! HexLoops X-Sub is completely free, and it offers a surprisingly straightforward approach to making sub-bass without the complexity of additional synthesis controls. When you need solid, low-end bass with minimal fuss, it's a great choice.

Getting Your Sub-Bass Right

The very low frequencies we refer to as "sub-bass frequencies" are the ones that give your tracks body and depth. With the right knowledge, producing and mixing sub bass doesn't have to be difficult. Make sure you're using a decent set of headphones or studio monitors that can produce the lowest note in your track and make sure you're studio is treated in such a way that you can hear these frequencies accurately

Once you've done all that, you'll be ready to produce music with all the womp and beef of your favorite artists!