As the low-end foundation of any beat-driven track, it’s imperative that the kick drum and bass are always rock solid and perfectly integrated, rather than fighting for space at this crucial and headroom-devouring end of the sonic spectrum. Here are some tricks and techniques you can draw on to make sure yours fit the bill.

Get A Subwoofer And Put It In The Right Place

Equipping your studio with a subwoofer is obviously going to make mixing the two lowest-frequency components of your tracks considerably easier. However, the monitoring efficiency of any sub is highly affected by its placement in the room, and the last thing you want to do is overstate the bass, which can easily happen if you don’t get the box producing it in the right position. Ideally, your sub should be in between your main speakers, just off-axis from the centre and slightly away from the front wall of your monitoring space – move it around within that range to find the sweet spot. Also, to get the most out of a sub and minimise standing waves, bass traps should be installed in the corners of the room.

If a subwoofer isn’t an option, a high-quality pair of headphones with good low frequency response can make for a just-about acceptable substitute when you need to get a better impression of what’s going on in the sub bass range than your monitors can report – just for occasional checking, though; don’t monitor through cans alone.

Address Timing And Phase

The two most important considerations when mixing the bass and kick are maintaining the independent yet clear audibility of each, and ensuring that both coincide (or not) consistently and cohesively, thereby avoiding wild jumps in volume and low-frequency build-up from note to note. Both of these factors are at least partly moderated by the relative timing of the two parts, which is easily edited in your DAW.

If you’re dealing with live recordings, hopefully the bassist and drummer nailed the recording on the day, so you can leave the two tracks alone on the timeline (apart from nudging any overt timing discrepancies into place), and move on to dynamics and EQ. If your recorded or programmed parts are exhibiting obvious clashing or nullifying when both instruments land at the same time, though, it could be because their waveforms are moving in opposite directions at the transients, or that the energy of the two signals is excessive when they’re perfectly stacked. Try shifting the offending bass notes, be they MIDI or audio, very slightly until the two waveforms line up in terms of polarity (ie, both peaking together, not one peaking while the other one troughs) or the instruments disconnect enough to bring them under control. We’re talking very small offsets, though – nothing big enough to affect the perceived timing of the rhythm section – and unless your drum track is characteristically loose, the temporal accuracy of the kick should never be compromised, so move the bass, not the kick.

Shortening long bass notes (especially those that sustain through off-beat kick drums) or kick drum tails can also prove an effective tactic for tightening up the low end of the mix. Fade them out if they’re audio, shorten their MIDI notes and/or envelopes if synthesised or sampled.

Equalise And Unmask

The reason why mixing kick drums and basses is a subject worthy of articles such as this one is that they’re a natural and essential partnership that necessarily occupy a common frequency range. To that end, some form of equalisation is invariably called for to minimise masking – that is, the highly detrimental ‘muddying’ that occurs when two sounds occur at the same frequency, particularly when one is louder than the other. There are no hard and fast rules here, as EQ is heavily dependent on the source material, but in planning the requisite cuts, you’ll need to decide which component should be dominant in any given frequency range and attenuate the other accordingly – the idea is simply to have the two sounding like they’re working together, not competing. Specialist EQs such as Sonible’s smart:EQ 3 and the Masking EQ and new Unmask module in iZotope’s Neutron 4 can be very helpful here.

It’s often worth playing around with high-pass filters on one or both elements, too, as rolling off the sub bass (at somewhere between 30-50Hz) on one can give the other the low-end room it needs to really come across as intended. Similarly, whether or not to high-pass everything else in the mix to make room for the kick and bass is a controversial topic, but there’s no reason not to at least try it on any part that feels like it’s extending further downs into bass territory than it needs to.

Sidechain The Bass

When it comes to cleanly separating the kick and bass so that the former delivers the desired punch and impact, there’s probably no more effective a solution than the ubiquitous production technique of ‘sidechaining’ or ‘ducking’. Quite simply, this involves keying the sidechain input of a compressor plugin inserted into the bass channel off the kick drum, so that the bassline is lowered in volume (‘ducked’) whenever the kick hits. The amount of volume reduction is set with the compressor’s threshold and ratio controls, and the compression envelope is used to shape the dynamic contour of the bass around the kick.

For a more nuanced approach, make that compressor a multiband model and you can duck just the lowest frequencies in the bass, which might be all that’s needed to enable the kick to cut through cleanly. Or, if you need more precision, use a sidechain-enabled dynamic EQ instead. And if you really want to make life easy, avail yourself of Cableguys Kickstart 2 plugin, which automatically applies a ducking volume curve to your bass (or other) part, either cyclically or triggered by audio or MIDI input.

Make Them Mono

Finally, unless you’re aiming for something decidedly unusual, everything in the mix below around 200Hz should be in mono and panned to the dead centre of the stereo field, and that, of course, primarily means the kick drum and bassline. As well as the fact that frequencies that low just sound weird and distracting when widened or panned, and cause phase issues when collapsed down to mono (by the average club PA system, most pertinently), the foundational role of the two drivers of the rhythm section clearly demands their centrality. If your bass does have a stereo component that you don’t want to lose (chorusing, say), use a mono filter plugin such as Nugen Audio’s, er, MonoFilter to mono-ise the signal only below a specified frequency.

Tell us about your approach to mixing kick drums and basses in the comments.