Preparing your mix for mastering: mixing in the low end
In this series, we’re examining how to best prepare your mixes for the mastering process, by looking at some of the most common problems I see with DIY mixes coming into my mastering studio.
Next up: sending a mix with an uncontrolled low end up to your mastering engineer. We all want a nice, thick, warm low end in our music, but how we achieve that can sometimes be counter-intuitive.
Quick solutions for better low end
During mixing, always use multiple reference points when attempting to evaluate the low end.
Be careful when using headphones as your primary low-end reference, as any headphone (no matter the price) will be less accurate in the low end compared to using speakers inside a properly controlled acoustic space.
A real-time analyzer can be a helpful tool to visualize sub bass sounds that you might not be able to accurately hear inside your bedroom, or when mixing on your headphones.
To achieve a nice warm mix, much less of the sub area (20-40 Hz) is necessary than you might think. This is somewhat musical style dependent, but we always want to strive for a balance of thickness and focus in the low end of a mix.
More in-depth discussion below.
Why is the bass area so hard to mix well?
If you’re mixing on your own, trying to learn by watching Youtube videos, without the benefit of a quality education in professional audio, it’s easy to make mistakes in the bass area. There’s two primary reasons for this:
1) Acoustics issues that mask bass frequencies are especially egregious when working inside small rooms on budget gear. A cheaper set of speakers will generally not be able to reproduce many low frequencies accurately enough for a professional quality sound. That may be ok when you’re listening to music as a consumer, but when we’re making the music we need to be able to hear everything we’re doing clearly.
And, the acoustics of your room itself can also strongly mask the low end and make the low end sound much softer than it really is, if you don't spend money on acoustic treatment and also learn how to design and install that treatment properly.
These issues in combination mean that you often won’t even hear any low-end mistakes you’re making, as you’re making them. Inaccurate equipment, combined with an inaccurate acoustic space, equals inconsistent, inaccurate mixes.
It’s very common for DIYers new to music production to spend hours on a mix, only to be surprised when their low end is suddenly sounding way too loud when they first play back their music in a different environment then they’re used to (like in the car).
2) Solutions for making a mix thicker and warmer are counter-intuitive.
If you want your mix to sound bass-ier, you should just turn the bass up more, right? This makes logical sense, but in practice the solution to better sounding bass is often more focused sounds in the bass area, not just louder bass.
You’ll often find that cutting conflicting low-end frequencies in other instruments will make your bass instruments sound not only louder, but clearer and more natural at the same time.
Simply turning up the bass by itself won’t solve any frequency conflicts in your mix, it will just make those conflicts sound louder and worse. The result is often the opposite of what you were intending: an artificially boosted bass area without also doing any clean-up work can leave your low end sounding muddy and unfocused.
Diagnosing a mix with uncontrolled low end
A real-time analyzer (RTA) can be a very helpful tool in the recording studio. A real-time analyzer is a metering tool that shows you the frequency response of your mix in full, as it plays back in real time. Apple’s Logic Pro software has one these built into its free Multimeter plugin.
If you’re working inside of a room that’s masking the lowest of the low end, using this tool might be the only way you’d know if you had any problems in the sub bass area. Your ears alone won’t tell you, if the room itself and/or your speakers are making your low end sound much softer than it actually is.
Here are some visual red flags to look for when using a real-time analyzer to check your mixes. If you see any of these, you might want to double-check some of your low-end EQ choices, and see if you can’t clean things up a bit.
The DIY low end example
A multimeter reading of the low end of track, mixed DIY style
In this example, we’re looking at the low end (16 Hz-200Hz) of a song mixed DIY style on headphones, using budget consumer-level gear.
And, using our RTA tool, we can see frequencies we might not be able to easily hear. In this case, we can see a relatively high amount of sub area thwub between 16-40 Hz. Keep in mind, humans can only hear down to 20 Hz, and many consumer-level speakers can only reproduce sound down to about 40 Hz without a subwoofer.
So, it’s possible the mixer here was completely unaware of the amount of low end mud they were leaving in their mix. If they were relatively inexperienced, and using budget gear, they probably didn’t even hear those frequencies when they were working, because their gear couldn’t reproduce them.
The end result? A mix with a loud, muddy, unfocused low end that will sound inconsistent across different types of playback equipment.
The pro low end example
A multimeter reading taken from the Taylor Swift song “Down Bad”
Here’s a multimeter RTA reading taken from the Taylor Swift song “Down Bad”, which I think many would agree is a track with a very focused and thick low-end sound.
Note: the area below 30 Hz is about 20 dB lower in volume compared to the previous example. That may not seem like much, but keep in mind that decibels are not a linear scale, and decibel changes always look smaller numerically than what they sound like in the real world.
In this case, 20 dB reduction in low end mud would sound well over twice as soft, compared to the DIY version!
More items of note: the rest of the low end from 60 Hz-250 Hz isn’t just a rectangular block of noise. Instead, this entire sonic region has been sculpted and carved out by the mixer in order to allow different low end instruments to ring through more clearly.
Technical vs. stylistic choices
I also want to emphasize that we’re not making any stylistic or musical judgements here. Neither of these two examples is better or worse music than the other.
There are lots of examples of certain styles of music being intentionally left a bit muddy during the mix. And, a hyper-clean pop music mixing style isn’t necessarily the right creative choice for every song or every artist.
I’m showing these differences simply to help tie the creative choices and the technical processes that achieve them together, to encourage more creative control and to give you more options when you’re making your music.
Affordable solutions for a better low end
So, how do we develop more creative control over our low-end, practically speaking?
Many of the traditional ways of achieving a more accurate bass response in your music room tend to be rather expensive. They often only make sense if your goal is to build out a professional recording studio as a business that generates income.
Acoustic room treatment properly designed and applied, use of subwoofers as part of a full-range monitoring system, and higher end speaker systems with better low-end response are all some of the best ways to get a more accurate low end in your music space. But, all of these solutions tend to be quite pricey.
For your typical singer-songwriter working from home who’s looking for a more affordable option, here’s a simple solution: use multiple reference points when mixing.
When you’re working, don’t use just a single set of headphones. Instead, check your work on 2-3 different types of monitoring references.
Maybe it’s one set of nicer headphones, one set of cheaper earbuds, and a basic set of decent speakers, all used in combination. If your music sounds relatively consistent between all of these different references, you’ll be in a much better place.
This solution won’t always get you 100% of the way to a professional sounding end product, but it will allow you to improve things significantly, at much less cost then a fully professional studio build-out.
