Keeley Bassist Owner's Manual - Starting Out / Basic Setup:

STARTING OUT / BASIC SETUP:

• Setting the Threshold:   The Threshold control is, in most cases 

the first control to set on a compressor. Signals that surpass the 

threshold level in volume will be reduced by the factor set on 

the compression control, all signals that don’t meet or exceed 

the threshold level will pass through completely unprocessed. 

To begin set-up, start with gain set at a moderate level, and 

compression set to 1:1. Play music through the pedal noting when 

the threshold indicator changes from green to red. The threshold 

indicator should not stay lit the entire time in most situations. 

For protection against higher than usual peaks, or to use as 

a completely transparent limiter, adjust Threshold to a point 

where the indicator turns red only under the loudest and most 

extreme circumstances, i.e. very hard picking attack, slaps, etc. For 

noticeable compression effects, or “always active” compression 

sounds, adjust Threshold to a level where every note played 

causes the indicator to turn red. 

• Setting the Compression (Ratio) control:   The compression 

control sets the amount of gain reduction that will occur past the 

Threshold level. The ratio, refers to the number of decibels that 

must be introduced over the threshold level to produce a 1db 

increase in output level. So, at a 5:1 ratio, every 5db of increase 

in the level entering the compressor above the set Threshold 

will produce 1db more output. While this sounds like a very 

simple concept, the effects of this can be quite complex. Higher 

compression levels will produce a more noticeable “squish” and 

will limit dynamics. The lower the compression level, the less