Punching holes in your bassline
We’ve seen how you can avoid overloading the bottom-end of your mix by EQing kicks and basslines to prioritise frequencies in one sound over frequencies in the other. This works particularly effectively if you don’t want to make one instrument more important than the other but you’re looking for more of a partnership between the two sounds instead, drawing out their respective strengths. However, if you do decide that, for example, your kick needs to take priority over your bassline, there is a simple and highly effective way to ensure that every time the two notes happen together, the kick wins the volume battle. This can be achieved via the use of a sidechain compressor placed over the bass sound. The sidechain signal is fed to it from the kick drum so that every time it plays, the compressor (and therefore the volume) of the bass sound drops dramatically.
To set this up, you’ll need to route the signal from your kick drum to the input of the compressor employed on your bassline’s channel. How this is done varies from one DAW to another, so if you can’t route the output directly, set up an auxiliary buss send from the kick channel. Then mute the output of this auxiliary so it isn’t sent to the speakers, before routing its internal signal to the bassline’s compressor. You can then decide how ‘extreme’ the volume dip will be on each bass note; for heavy treatments, set a low threshold point and a high ratio. For subtler ones, lower ratios and higher thresholds will help. You also need to set attack and release times to taste – experiment here, as different tempi and the pattern of your bassline will suggest different values.
If you want this ‘ducking’ technique to continue through passages where the kick drum drops out but the bass continues, duplicate the kick track, make it play constantly and then silence it (as described above). Use this ‘silent trigger’ as your sidechain source instead.