User Guide

4.14 Threshold.
The Threshold is the point measured in decibels that any compression comes into
operation. The Threshold control is variable from +10dB in the most anticlockwise
position to -20dB at the most clockwise position. Any signal below the Threshold
passes through the unit unaffected; while signals above the Threshold are reduced in
gain (and are thus ‘compressed’). This does depend on the Soft or Hard knee to
some extent as the Soft knee is more gradual around the Threshold point.
Unlike some compressors, the Threshold control on the 5052 starts at a ‘plus’ value
in the counter-clockwise position, and decreases to a ‘minus’ value as you rotate the
control clockwise. The reason for this is as you turn the Threshold control on the
5052 clockwise (i.e. towards the negative region) then the degree of compression will
increase. We think this is logical, whereas the common method of turning the control
‘down’ to achieve more compression is not - but beware, some other compressors
may work in the opposite direction!
4.15 Ratio.
Once the input signal has crossed the threshold, the degree of gain reduction is
determined by the Ratio control. The Ratio control is calibrated in decibels and is
simply the change in output level that results from a given change in input level. An
uncompressed signal will have a 1:1 compression ratio - every 1dB change in input level
results in the same 1dB change in output level. A compression ratio of 1:3, for
instance, means that a 3dB change in input level will only give a 1dB change in output
level. For more severe compression, simply turn up the Ratio control.
The 5052 offers a wide range of ratios from 1:1.5 (very gentle compression) through
to 1:30 (very severe compression).
4.16 Attack and Release.
The Attack time sets how quickly the compression is applied once the threshold has
been exceeded, and the Release time sets how quickly the compression is released
(and the signal returns to normal) once the signal drops back below the threshold.
The 5052 allows fully variable control of Attack and Release times between
‘Slow’ and ‘Fast’. For Attack this covers the range 0.4mS to 40mS, while the Release
control spans 40mS to 4S. There is an element of automatic operation of the Attack