Guide

How to sidechain the bass to the kick

When the kick and the bass land together they compete for the same low frequencies, and the kick loses its punch. Sidechain ducking turns the bass down a few decibels each time the kick hits and lets it back up in between. Here is how to set that up in Zammoth, by hand or by asking for it.

The Duck device on a bass track, triggered by the drums: each drum hit shows as a spike, and the bass dips under it by up to 5.8 dB. — The Duck device on a bass track, triggered by the drums. The upper lane is the trigger's level against the threshold; the lower lane is how far the bass is being turned down.

By hand, in two steps

Add Duck to the bass. Select the bass track, open the browser's Devices tab and double-click Duck, or drag it onto the track.
Pick the trigger. The menu on the device lists every other audio track. Choose the kick. If your drums are one track, choose that. The bass starts ducking straight away.

That is the whole routing. There is no bus to build and no sidechain input to patch, and ⌘Z takes it back.

The four settings

Control	Range	What it decides
Threshold	−60 to 0 dB, starts at −30	How loud the kick has to be before the bass moves. Lower it until every kick is caught.
Depth	1 to 12 dB, starts at 6	The most the bass is turned down.
Attack	1 to 100 ms, starts at 5	How fast the bass gets out of the way.
Release	20 to 1000 ms, starts at 150	How fast it comes back.

The defaults are a sensible place to start. Two things are worth setting by ear:

Depth. For a bass that should still sound solid, 3 to 4 dB is often enough to clear the kick. For the pumping effect you hear in dance music, go deeper.
Release. The bass should be back before the next kick. At 120 BPM a kick on every beat arrives every 500 ms, so a release well under that keeps the line moving. Too long and the bass never fully returns.

You can see whether it is working. A dot lands on the device each time the duck engages, so a kick that slips under the threshold is easy to spot. Drag the dashed line on the display to move the threshold.

Or let the engineer set it

Press SC Auto on the device. Zammoth's engineer looks through the mix for the strongest low-end clash involving that track, picks the trigger, sets the four controls to suit the audio and tells you the numbers it chose. If ducking makes no sense on that track, it says why and takes the device off again.

You can also skip the device and just say it:

duck the bass under the kick

Either way the result is an ordinary Duck device with ordinary controls, so you can adjust it afterwards or undo it. The engineer needs an Anthropic API key; doing it by hand does not.

Good to know

Duck goes on tracks, one per track. It does not go on a bus, a return or the master.
Setting the trigger to none switches the ducking off and keeps your settings for later.
The reduction shows in the mixer, in the track's gain-reduction meter.
Ducking is not only for bass. The same device clears space for a vocal under pads, or for a voice-over under music.

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