Marani CLP-2600, User Manual

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Before to proceed illustrating the editing and setting of the AGC parameters, it is good to remind
how an AGC
(
Automatic Gain Controller
)
is working
Referring to the following picture
The AGC is an Expansion
/
Compression process applied with pretty slow Attack and Release times
to the INPUT signal of a Unit
,
in order to maintain the average amplitude of the OUTPUT signal at
a defined level
,
independently from the averaged amplitude of the input sources
.
For this purpose
,
the AGC has to be able to expand the input signal
,
there where the average of
the related output signal is below a defined Threshold (Exp Thr
),
and to maintain the expanded
signal at a constant expansion level when the averaged signal is beyond a defined Threshold
(
Thr
Hold
).
The AGC implemented in the CLP2600 is acting on the evaluation of an input signal which is ana
averaged one on a 50ms time frame
,
and representing actually the RMS value of the input signal
itself
,
so to make more Musical the AGC action
.
If the output signal of the AGC process will exceed then a defined Threshold
(
Cmp Thr
),
so
becoming too loud
,
a compression process is occurring
.
The Speed and the amount of the Expansion can be defined through the Exp Time
'
and Exp
Ratio parameters
,
so as the Speed and the amount of the Compression can be defined through
the Cmp Time and Cmp Ratio parameters
.
When the Signal coming out from the AGC process
(
Output
),
applied to the AGC input
,
is above
the Exp Thr and below the Thr Hold
,
it is expanded up to the max expansion coefficient
defined by the Exp Ratio
.
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