Extron electronics DMP 64 User Manual page 101

Feedback Suppressor Block
The feedback suppressor processor block, when inserted,
detects feedback on a live microphone channel, and uses a set of fixed and dynamic filters
to counteract the detected feedback frequencies. It is possible to achieve an additional
3 dB to 9 dB of mic gain in conditions where feedback may have otherwise prevented
these levels. See Feedback Suppressor
Dynamics Block (2)
The two dynamics processor blocks, when
inserted, each provide one of four dynamic
processors. A dynamic processor alters the
dynamic range of an audio signal, the difference
between the loudest to the quietest portions
of the signal. Click on the desired dynamics processor to select it. See
additional information.
After selection, parameters can be changed in the dialog box, customized to the processor,
by double-clicking the processor block.
•
Automatic Gain Control (AGC) — AGC adjusts signal gain relative to the strength of
the incoming signal to achieve consistent volume. Below the set threshold, the signal
is not affected. Above the threshold, weaker signals are boosted up to the maximum
gain setting to reach a user-defined target level. As the signal level approaches the
target level it receives less gain or no gain at all. Once the signal level reaches the
target level all gain is removed.
• A window range, indicated by the two yellow lines, is also applied above and below
the target level. Below the lower line maximum gain is always applied to the signal.
When the signal reaches the window, gain control begins scaling in a linear fashion to
achieve smoother results as the signal reaches the target level.
The default threshold is -40 dB. The default target level is -10.0 dB. The default gain
and window are 12.0 dB.
• Compressor — The compressor regulates signal level by reducing, or compressing,
the dynamic range above a specified threshold. The signal input level to output level
ratio determines the reduction in the dynamic range above the threshold setting. In
the adjacent example, with a ratio setting of 2.0:1, once the threshold (-30 dB) level is
exceeded, for every 2 dB of input above that level, the compressor outputs 1 dB.
Compression is commonly used to keep mic levels within an acceptable range for
maximum clarity. A compressor can also make softer sounds louder by reducing the
dynamic range and raising the output level (referred to as "make-up gain"), or by
increasing the input signal and reducing the louder portions of the signal. This has the
effect of making louder portions of a signal softer. Similar to a limiter, compression
also can be used to protect a system or a signal chain from overload.
The default threshold is -30 dB and default ratio is 2.0:1.
for additional information.
DMP 64 • Software Control
Dynamics for
95