Mix bus glue: how to make a FET compressor ignore the kick

"A FET compressor is too fast for the mix bus." You will read that on almost every mixing forum, and with the classic design at its default settings it is often true. Three changes fix it: a softer revision, a slower attack and a sidechain filter that stops the kick from running the show.

Here is the mix bus compression setting we start from: AE at ratio 4, ATTACK 2, RELEASE 5, 1 to 3 dB of gain reduction, and the sidechain filter at 120 Hz with the steep 24 dB/oct slope.

Why the kick takes over

The kick carries most of the energy in a modern mix. A compressor on the bus hears it louder than anything else, so it clamps on every kick. The whole mix ducks in time, and you hear pumping.

The sidechain HPF in the ADVANCED drawer removes the lows from the detector only. At 120 Hz with the 24 dB/oct slope, the compressor responds to the music, while the kick passes through untouched.

The glue setting

AE is the softest revision, with ratios of 2, 4, 8 and 20 and a slower top attack. ATTACK 2 lets transients through, so the mix keeps its punch. A small positive TILT tips the detector toward the upper mids, so vocals and snare do more of the driving.

Set the filter by ear

Press LISTEN while you move the HPF knob. You are now hearing the detector, not the mix. You want the kick clearly reduced, with the snare and vocal still present. Then switch LISTEN off.

Judge it honestly

On the mix bus every decibel counts, and louder always sounds better. Use ☰ › Level-match A/B, or AUTO GAIN, before you decide. If the mix sounds better at matched level, keep it. If it only sounds louder, back INPUT off.

Two more checks:

• Watch the needle. It should move gently with the phrases, not jump on every beat.
• Listen to the vocal. If it drops when the chorus hits, the compressor is working too hard.

Drum bus variation

The same idea works on a drum bus with a bit more reduction. Try Rev D (LN), ratio 4, ATTACK 2, RELEASE 6 and the HPF at 80 Hz, with 3 to 5 dB. For more energy, blend it in parallel with MIX, as described in parallel drum compression.