Allen&Heath GL4000 USER GUIDE - Manual (Page 24)

23
MONO
2-TRACK STEREO RETURN - The incoming
level can be trimmed from OFF to +10dB gain
and routed direct to the LR mix for intermission
or recording replay. Monitor the signal post
LEV trim and pre REPLAY switch using
STEREO PFL which automatically overrides
the signal in the headphones and local monitor.
AFL/PFL INDICATORS - Large red LED
indicators show when AFL or PFL is selected.
MONO METER - The MONO METER follows
the post fade mono mix signal and is interrupted
to show the AFL or PFL signal when selected.
PFL INTERRUPTS AFL - Pressing a PFL
switch automatically overrides any selected
AFL. This is most useful in stage monitoring
when you may wish to continually monitor a
selected stage mix using AFL. You can quickly
check the channel signals by pressing PFL
which cuts out the stage mix monitor signal
while selected.
STEREO PFL METERING - Press the switch
above the mono meter to allow any selected
PFL to override the LR meters. These meters
will display PFL in stereo if a stereo source is
selected. If a mono source is selected both
meters display the mono PFL signal.
STEREO/MONO COMPATIBILITY - You can
display and listen to the mono compatibility of
your stereo sources by selecting a stereo PFL.
The L and R meters display the signal in stereo.
The M meter displays the LR sum (mono)
signal. A low M meter reading compared with
LR meters can indicate a phase problem
between L and R. This can be checked and
corrected using the stereo channel ØR switch.
You can listen to the signal in mono by pressing
the STEREO/MONO switch in the console
monitor section.
TALKBACK - Plug in a microphone and
adjust TB LEV to talk to the outputs you select
on the talkback assign switches. An internal
link assigns +48V phantom power if required.
Talkback will be activated to the selected
destinations when you press the large TALK
button. If any destination is selected the green
LED in the TALK button will light, useful if you
want to be sure that the talkback system is
made 'safe' during the show. You can talk to
the 10 auxes in any combination, to the M mix,
LR mix, all 8 groups together, and all 4 matrix
together.