drivers are frequently damaged, the whole system must be operated at a lower sound-pressure
level, or additional mid-range drivers must be added. By inserting an equalizer in the Sidechain
path to the 166xs, it can be made more sensitive to frequencies in the range handled by the
sensitive drivers. The system can then be run at higher levels and will only be dropped back
when damaging signals are present.
Using a Filter in the Sidechain Circuit
The results of inserting a filter in the Sidechain circuit are basically the same as obtained
with an equalizer, as previously described. Those frequencies passed by the filter are subject
to compression (or at least they are subject to considerably more compression than those
frequencies outside the passband). Because a passive filter can have insertion loss, it may be
necessary to lower the 166xs THRESHOLD setting to maintain a given amount of gain
reduction within the filter passband; this can be determined by monitoring the 166xs
THRESHOLD LEDs.
Pre-Emphasis for Broadcast Applications
By inserting a pre-emphasis filter network in the Sidechain path of a 166xs processing
pre-emphasized audio, higher levels can be run within the headroom limitations of the
broadcast chain.
Section 4
Operating Notes
20
dbx 166xs
