Allen&Heath GL4800 USER GUIDE - Manual (Page 23)

GL4800 User Guide 23
C 8
SIDE
L
SIDE
R
MIDDLE
CARDIOD
FIGURE-OF-8
STEREO
REVERSE
STEREO
MONO
L = M+S
R = M-S
SIDE
ABOVE
BELOW
SNARE
A B
SIGNAL PROCESSING
L R
L R
MONO
AUX
1
+6
+6
+6
+6
+6
+6
+6
+6
AUX
2
AUX
3
4
AUX
AUX
5
6
AUX
7
AUX
AUX
8
PRE
PRE
POST
POST
0dB
0dB
0dB
0dB
0dB
0dB
0dB
0dB
PRE
POST
+6
AUX
9
0dB
+6
AUX
10
0dB
ODD
PAN
L EVEN R
=
BAL
POLARITY POLARITY
XLR GAIN
PAD
MIC
LINE
HPF
+48V
POLARITY POLARITY
XLR GAIN
PAD
MIC
LINE
HPF
+48V
POLARITY POLARITY
XLR GAIN
PAD
MIC
LINE
HPF
+48V
+48V
HPF
LINE
MIC
PAD
GAIN XLR
POLARITY POLARITY
+48V
HPF
LINE
MIC
PAD
GAIN XLR
POLARITY POLARITY
+48V
HPF
LINE
MIC
PAD
GAIN XLR
POLARITY POLARITY
BAL
PAN
BAL
PAN
(R)
POLARITY
GAIN STEREO
WIDTH
PFL STEREO
DIRECT
L-R TO
XLR
STEREO
(R)
POLARITY
GAIN STEREO
WIDTH
PFL STEREO
DIRECT
L-R TO
XLR
STEREO
R
STEREO LINE
IN
L /MONO
R
STEREO LINE
IN
L /MONO
SEND
XLR
INSERT
RET
SEND
XLR
INSERT
RET
SEND
XLR
INSERT
RET
SEND
XLR
INSERT
RET
R
STEREO LINE IN
L /MONO
(R)
POLARITY
GAIN
STEREO
WIDTH
PFL STEREO
DIRECT
L-R TO
XLR
STEREO
SEND
XLR
INSERT
RET
SEND
XLR
INSERT
RET
R
STEREO LINE
IN
L /MONO
MIC LINE
IN
MIC LINE
IN
MIC LINE
IN
MIC LINE
IN
MIC LINE
IN
MIC LINE
IN
(R)
POLARITY
GAIN STEREO
WIDTH
PFL STEREO
DIRECT
L-R TO
XLR
STEREO
M-S Stereo Microphones
Stereo Microhones
This example shows two
cardiod microphones
arranged as an X-Y
coincident pair. This
minimises the phase
differences which can cause
problems when the mics are
arranged as a spaced pair.
The mic input stages are
patched into a stereo line
input for single fader control.
The second stereo channel
may be used for an
independent line input.
Above and Below Microphones
Here, two microphones are
used on the snare drum to
get the best balance between
stick sound and skin
resonance on top, and snare
sound below. Reversing the
phase of the lower mic can
compensate for the opposite
skin resonance between the
mics. Signal processing such
as noise gates can be
patched in as shown.
The M-S stereo configuration is often
preferred when simultaneous mono feeds
are derived from the stereo signal. Here,
a cardiod and a figure-of-8 mic are
positioned on the same stand. The
cardiod picks up the "middle" (mono)
signal, and the figure-of-8 the "side"
(stereo content). Stereo is extracted from
the mic signals by producing sum and
difference channels. When combined the
stereo content is cancelled out leaving
true mono. Balance the two faders to
achieve the desired image.