Orban 424A - Appendix Interconnections and; Stereo and Multichannel Operation; Speech-Activated Ducking

Stereo
And
Multichannel Operation
The
two
channels of the 424A may
be strapped by means
of the
INDEPendent/COUPLED switch to
assure stereo tracking and stable
imaging.
In
addition, any reasonable number
of
422A's or
424A's can be
tracked by respectively
paralleling
their
rear-panel STEREO CPL and GATE CPL terminals. All
compressor/limiter VCA's
will then
track
the channel requiring the highest
amount
of gain reduction.
Provided
that
the GATE
THRESHold
controls of all
units are
set
identically, all units will
remain ungated
provided
at least
one
unit
receives
sufficient input
level to ungate.
All operating controls are
usually set
identically.
The de-essers remain independent.
Speech-Acti
voted Ducking of Music
Speech-activated
ducking of
music is
one unusual
capability which requires
the
use
of
two (or more) channels
with the controls
set in a unique way. In this
broadcast-
oriented application, the level
of
the music in
the
on-air
mix is
automatically
reduced
whenever speech is present.
A 424A or
two
422A's, in
COUPLED or strapped mode, must be used.
Channel "A"
is
used for the speech,
and Channel
"B" for the
music.
Apply the
speech to Channel "A",
and adjust
the "A"
operating controls
to produce
fast
attack
and release times, with the compressor/limiter
OPerate/DEFEAT
switch
to OP. Set
the "A" GATE THRESHold control OFF (fully CCW).
Apply the music to Channel
"B", set
its compressor/limiter OPerate/DEFEAT
switch to DEFEAT,
and
set
its IDLE GAIN control to
"0".
Adjust the "B"
INPUT
ATTENuator
so that the
VCA LEVEL
meter never enters the
red even
on
the
highest peaks of
the
music.
Speech
appearing
at
the CH "A"
input at a
level high enough to cause gain
reduction
in
CH
"A"
will
cause equivalent
gain reduction in CH
"B",
thus
ducking
the music automatically
during speech. The
RATIO control determines if
the
music
level
is
reduced
in
direct
proportion to
the
speech
level
(high
RATIO), or
less than
proportionately (low RATIO). The setting of
the INPUT ATTENuator
primarily
determines the depth
to
which the music is ducked
(the more gain
reduction, the
more ducking).
The outputs of the "A"
and
"B"
channels (i.e., speech and
music) may be
mixed in
an
external mixer in any proportion
desired. The original speech
source may
even
be processed by another 424A with
different
settings, processed
by
other equipment,
or
left unprocessed.
By
analogy,
a similar setup
can
be used to modulate
any
signal
by
the envelope of
any
other signal. The range
of the
ATTACK and
RELEASE TIME
controls
define
the ability of
this setup to track rapidly-varying envelopes.
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