A compressor smoothes out your bass sound, or squashes it flat. Learn how to get the sound you want.
Music: Jahzzar, Please Listen Carefully; spinningmerkaba, Urbana-Metronica (wooh-yeah mix). Image: David Pacey.
- What is a compressor?
- Squashes signal that gets past a certain level
- Considered a must-have effect for bass, vocals, some other instruments too
- Dave, do you use one? What kind?
- Yes – Recent convert (back story)
- Aguilar TLC – Level/Threshold/Attack/Slope
- Paul, do you use one? What kind?
- Not when I’m practicing but almost all the time otherwise!
- Sometimes it’s the one built into my multi-pedal. I used to have an MXR pedal. I have an Alesis 3630 on an old amp in my office. And I have a Markbass tube compressor pedal I use sometimes.
- Think about it as turning down the volume when the signal gets loud
- This also means you can turn up the entire level without worrying about the signal going past a certain point
- Loud peaks get less loud, and quiet parts get less quiet
- Evens out your playing, but can that be a crutch?
- Some compressors have a simple control… more or less, one knob
- Most pedals or other units have multiple controls, let’s go through them
- This is how loud things have to get before you start clamping down
- Affected by how loud your bass signal is to start with
- How much to clamp down once you pass the threshold
- 2:1 means for every 2dB the signal would have gone up, it will only go up 1dB. 3:1 is even more clamping, and so on. (1:1 would be none.)
- How fast should the compressor jump on the signal once it passes the threshold?
- The faster the attack, the more the “pop” of a transient or peak will be smooshed out. Slower means more attack but at the risk of jumping out
- How fast should the compressor let go of the signal once it falls?
- Longer release means more sustain, shorter release is more natural
- Hard knee means the compressor pretty much follows the threshold setting more precisely
- Soft knee means it starts to react before the threshold, but is fully on by the time the threshold is reached
- Level, Output, or other makeup gain control
- Allows you to compensate for the squash in volume by turning everything up
- Indicator light or meter
- You can use this plus your ears to play with your compressor and listen to what happens as you play
- Try to use a consistent attack and playing style so you’re making a fair comparison
- Some meters use a “GR” setting, for Gain Reduction