Wheatstone Corporation D-7, Technical Manual, Page: 76 / 92

D y n a m i c s P r o c e s s i n g C o n t r o l G U I
page 8 – 7
D-7 / Nov 2006
Sometimes the gain reduction is
required to be subtle so as not to draw
attention to the fact that the expander is
in operation; under these conditions
shallow expansion ratios, such as 1:1.5
or 1:2 are preferred, as are restricted
depth - 6dB, or 10dB, is plenty and
makes a substantial subjective improve-
ment to the noise.
These, too, are the kind of settings
used for another application of an ex-
pander: effectively shortening an ex-
cessively long room reverberation time,
or an instrument’s ring-out that is overly
persistent. In these cases the threshold
is set somewhat higher, well up into the
desired audio levels - in this way the
attenuation becomes part of the overall sound, but the gentle ratio
prevents a sense of anything “odd” happening. Again, relatively shallow
depths of 12dB or so are plenty to achieve the desired effect.
More aggressive expansion, or “gating”, is accomplished with steep
ratios (1:3, 1:5) and with shorter open and close times than for “unobtru-
sive”. It is still best not to go overboard with depth - even just 14dB, 20dB
tops, is enough to make a signal “disappear” in the context of a mix; the
whole gating sound, especially surprisingly its opening, is less obvious
with shallower depth. Sometimes the “Surprise!” element is required,
though, for effect.