Manual-6
Making Connections
The C4 features auto balanced/unbalanced XLR and ¼" TRS
input and output jacks, permitting connection to virtually any
mixing console. Side-chain inputs are also auto balanced/unbal-
anced, on ¼" TRS only. Dynamics processors typically connect
using a mixing console’s insert points (send/return), although
they can be used in-line, such as when compressing or limiting
an overall mix, for example.
MIC INPUT
INSERT SEND
INSERT RETURN
INSERT SEND
INSERT RETURN
INSERT SEND
INSERT RETURN
INSERT SEND
INSERT RETURN
INSTRUMENT IN
SUB GROUP 1
SUB GROUP 2
CH 1 SIDE-CHAIN
CH 1 INPUT
CH 1 OUTPUT
CH 2 OUTPUT
CH 2 INPUT
CH 2 SIDE-CHAIN
CH 3 SIDE-CHAIN
CH 3 INPUT
CH 3 OUTPUT
MASTER
STEREO LINK
SLAVE
CH 4 SIDE-CHAIN
CH 4 INPUT
CH 4 OUTPUT
MIXER
C4
BASS
MIC
Figure . Connection to a mixing console.
MIC INPUT
INSERT SEND
INSERT RETURN
CH 1 SIDE-CHAIN
GRAPHIC EQ
CH 1 INPUT
CH 1 OUTPUT
MIXER
C4
6
–
4
2
1
±6
4
0
1
2
+
6
10
0
2
4
8
6
ME 30B
400
31.5
25
40
63
50
100
80
160
125
250
200
315
12.5k
1k
630
500
800
1.6k
1.25k
2k
3.15k
2.5k
5k
4k
8k
6.3k
10k
20k
16k
MASTER CONTROL
POWER
OL
LEVEL
RANGE
BYPASS
±12
12
–
8
5
2
8
0
2
5
MICROGRAPHIC
EQUALIZER
+
12
Figure . Using an external equalizer in the side-chain.
Front Panel Controls
Each channel of the C4 features the following meters and con-
trols:
Side-chain and Gain Reduction Meters
8
-3 -1
12
4
2
-6
-12
1
18
dBr
Reduction dB
TH
This triple-function meter displays the side-chain level, threshold
indication and amount of gain reduction being applied. It allows
you to see at a glance exactly what the compressor is doing at all
times.
Side-chain Level Display
In Compressor mode, the floating meter displays the side-chain
level
relative to the Threshold
(dBr), making it easy to gauge how
close the signal is to the onset of compression. The dBr indicators
light from left to right as the signal approaches the threshold. At
threshold, the yellow TH indicator is lit. Above threshold the
TH indicator remains lit and gain reduction occurs. Side-chain
meter ballistics follow the rms detector time constant of 30 ms.
In Dynamic EQ mode, the side-chain meter displays the
relative difference between the broadband program material and
the bandpass signal defined by the PEQ, as compared to the set
Threshold.
Example
: With THRESHOLD set to -15 dB, the TH indica-
tor lights when the sibilant portion of the program material is 15
dB below the broadband program material. If the sibilants are
18 dB below the broadband material, then the –3 dBr indicator
is lit.
Gain Reduction Display
The Gain Reduction meter displays the amount of gain correc-
tion presently applied to the signal, lighting from right to left as
the amount of gain reduction increases. In Compressor mode,
this meter display the amount of gain correction being applied
to the broadband program material. In De-ess mode. this meter
shows the amount of gain correction being applied to the dy-
namic EQ (DEQ) in the main signal chain. This meter does not
reflect any gain reduction occurring due to limiting.
Gain Reduction meter ballistics follow the actual gain cor-
rection value as determined by the THRESHOLD, RATIO,
ATTACK, RELEASE and KNEE controls. Gain reduction may
be indicated when the Threshold indicator is off, as attack and
decay rates may dictate continued gain reduction even when the
rms level is below threshold.
