How to compress bass with a FET compressor

For bass DI, use a clean revision at ratio 8, a slow attack (2) so the pluck gets through, and a slow release (3) so the compressor does not chase each low-frequency cycle. Aim for 4 to 6 dB of gain reduction.

Bass is the instrument most people over-compress or under-compress. The notes jump in level from string to string and fret to fret, and in a mix those jumps make the low end feel unstable. A FET compressor fixes that quickly, but its speed needs care on low frequencies.

The starting point

ATTACK 2 is the slow side of a fast compressor: the first few milliseconds of each note pass before the clamp, so the pluck stays. Ratio 8 holds the sustain steady. XFMR a little above its default thickens the bottom.

Why release time makes bass growl

A 50 Hz note has a cycle 20 ms long. If the release is faster than that, the compressor lets go and grabs again inside a single cycle. That bends the waveform, and you hear it as growl and distortion. Sometimes that is the sound you want. Often it is not.

Measured in PINCH-76 Rev D (LN): at 8 dB of reduction, distortion at 1 kHz is 0.08 %, but at 100 Hz it is 0.69 %. That is the hardware's well-known growl on heavily compressed bass. Keep RELEASE on the slow side for clean bass; turn it faster on purpose when you want grit.

Clean or dirty: pick by revision

Each revision handles low end differently; the revision guide has the measurements.

Goal	Revision	Settings
Clean, solid DI	Rev D (LN)	Ratio 8, ATTACK 2, RELEASE 3
Grit for rock	Rev A	Ratio 4, ATTACK 3, RELEASE 4 to 5
Bass with attitude	Rev A, all-buttons	ATTACK 3 to 4, RELEASE 4 to 5, 4 to 8 dB
Synth bass, gentle	AE	Ratio 4, ATTACK 2, RELEASE 4

On a busy track, ratio 4 with 6 dB of reduction often beats ratio 8 with 3 dB. If the low strings still disappear, reduce the gain reduction before you reach for more drive.

Duck the bass under the kick in FL Studio

Sidechain compression makes room for the kick by turning the bass down a little every time the kick hits.

1. Put PINCH-76 on the bass mixer track.
2. Select the kick track, right-click the small arrow under the bass track and choose Sidechain to this track.
3. In the wrapper settings (⚙), Processing tab, set the sidechain input to the kick track's number.
4. In PINCH-76 open ADVANCED and switch EXT on. LISTEN plays the key so you can check it.
5. Set ATTACK fast (6) and RELEASE to taste; RELEASE 4 to 5 follows most tempos.

Quick fixes

You hear	Try this
The bass distorts or growls when you don't want it to	Slow RELEASE by one or two steps
The pluck has disappeared	Slow ATTACK to 1 or 2
Compression reacts to string noise, not the notes	Switch the sidechain filter off
Some notes still jump out	Fix them with clip gain first, then compress
The low end sounds thin after compression	Raise XFMR a little, or reduce the gain reduction