This is about basslines, not (necessarily) the frequency range. The bassline is the harmonic foundation of a track. A solid mix often needs a solid bassline.
So how do you get there? How do you stop your basslines from sounding weak or flabby? Here are some techniques to consider:
This is the big one.
A lot of the time, EQ is all you need. The trouble is, each situation is different. I can’t tell you where to boost and where to cut without hearing your track.
Because EQ is relative, the right settings depend entirely on the sound of your bassline and the direction of the mix.
Pay close attention to how the kick and the bass interact. In some cases, it makes sense to have a bass with character voiced above a deep kick; in other cases, it makes sense to have a deep bass-voiced under the kick.
Good monitoring is crucial here because you’ll have to balance the tone across a wide range – sometimes all the way from subbass up to the top of the mix.
And most lower-budget monitoring environments are pretty bad at accurately representing the critical range from the bottom through the lower mids.
You can’t boost what isn’t there. Often a bass sound will have a great character in the mids but doesn’t have a solid bottom end.
Similarly, it’s common for a bass sound with a solid bottom end to be missing character in the mids.
By layering two complimentary bass sounds, you can have the best of both worlds! Be careful though – effective layering can very easily take over the whole mix.
When layering bass sounds, it often helps to filter the layers. For example – an upper layer that adds a lot of character in the mids may have a weak or inconsistent low end.
By using a high pass filter to cut out that low end, a lower layer can be much more focussed and provide a stronger sound.
Similarly, it often makes sense to use a low pass filter or dramatic EQ to take the mids out of the lower layer so that the upper layer can punch through more effectively.
Lastly, don’t forget to pay attention to the relative levels of each layer. Often a mix needs one layer to be dominant – the other layer(s) usually can be much quieter and still provide enough definition and size.
This is a magic trick for making almost any sound bigger – not just bass. When using saturation, it’s important to keep in mind that you don’t need much for it to be effective (unless you’re going for a fuzzy distorted bass).
A little bit goes a long way. Also, different saturation tools respond very different to bass. It’s often useful to have several different options.
Some saturation tools will rob you of low end, others will get too fizzy. A technique that often works well is to mix a saturated version of the bass with the original clean version and to apply a low pass filter after the saturation. This will avoid the high-end fizz produced by some saturation tools, and will often thicken up the lower mids.
4. Stereo width
Simply, wider sounds are often perceived as being bigger. It’s important, however, to find the right balance – too much stereo widening will reduce the body and foundation of the sound. It often makes sense to widen the mids and/or top end, while keeping the low end narrow.
5. Chorus / unison detuning
Similar to stereo widening, the use of chorus and unison detuning can make a sound bigger.
And again – the balance is in using enough to make the sound bigger without reducing the body and foundation. Applying chorus or unison detuning to the mids and/or top end will avoid the bottom getting washy.
6. Sidechain compression
This is a popular technique – especially when triggered with the kick drum. This allows the bass to be louder when the kick drum isn’t sounding.
By making the kick and bass take turns, the overall low end of the mix can be more consistent and powerful. It’s a distinctive sound, however, and isn’t appropriate for all kinds of music – particularly when the bassline has a distinctive rhythmic pattern. If in doubt, try it out.
7. Bonus technique: Bass amp / cabinet
Amp sims aren’t just for guitars! Processing a synth bass with a simulated bass amp can provide a dramatic tonal change. Saturation/overdrive and compression are also often included as part of the package.
This technique isn’t subtle though – don’t reach of an amp sim if your bass is already pretty close to what you want. Amp sims are great when you have a weak or lousy bass that needs some major transformation.
The sound of the cabinet can also help keep the energy of the bass consistent across a wide range of notes – this can be handy if your bassline is melodic or jumps around a lot.
8. Bonus technique: Compression
I think compression on synth bass is overrated. Most synths can be set up to provide a consistent level and punchy envelope without compression.
Where compression shines, however, is on electric (or even acoustic) bass when performed by a musician. When working with recordings like this, applying the compression first will make the sound more consistent and help later processes – especially saturation.
With these techniques and some practice, you should have no trouble getting your bass to support the rest of your mix.