Safety Notes; Applications - IMG STAGELINE MFE-16M Mode D'emploi

2 Safety Notes

The units (feedback eliminator and power supply
unit) correspond to all relevant directives of the
EU and are therefore marked with
WARNING The power supply unit uses dan-
gerous mains voltage . Leave ser-
vicing to skilled personnel only .
Inexpert handling may result in
electric shock .
•
The units are suitable for indoor use only . Pro-
tect them against dripping water and splash
water, high air humidity and heat (admissible
ambient temperature range 0 – 40 °C) .
•
Disconnect the power supply unit from the
socket immediately
1 . if one of the units is visibly damaged,
2 . if a defect might have occurred after a unit
was dropped or suffered a similar accident,
3 . if malfunctions occur .
In any case the units must be repaired by skilled
personnel .
•
For cleaning only use a dry, soft cloth; never
use water or chemicals .
•
No guarantee claims for the units and no li-
ability for any resulting personal damage or
material damage will be accepted if the units
are used for other purposes than originally
intended, if they are not correctly connected
or operated, or if they are not repaired in an
expert way .
If the units are to be put out of oper-
ation definitively, take them to a local
recycling plant for a disposal which is
not harmful to the environment .

3 Applications

The MFE-16M is a digital feedback eliminator spe-
cially designed for PA systems . It is used to elimi-
nate acoustic feedback . Feedback occurs when a
signal picked up by a microphone is amplified and
reproduced by speakers and then picked up again
by the microphone . Due to the loop created, the
signal is amplified again and again resulting in an
annoying whistling .
To eliminate feedback, the unit monitors the
input signal . When feedback occurs, it filters out
a narrow band of these feedback frequencies
via up to 12 notch filters for each channel . Thus,
a higher volume for PA applications is possible .
4 Connections
Insert the feedback eliminator into the signal path
where feedback is most likely to occur, e . g .
.
1 . between the microphone preamplifier and the
power amplifier
2 . for a mixer: into the input channel for the vocal
microphone (channel insert)
3 . for a mixer: into the subgroup for the vocal
microphones (subgroup insert)
4 . for a mixer with monitor output to reproduce
the sound for the musicians: between the
monitor output (e . g . Prefader Aux Send) and
the power amplifier
To prevent elimination of deliberate feedback
signals (e . g . from electric guitars), do not route
these signals via the MFE-16M . The easiest way
to do this is to connect the eliminator to an
insert jack of an input channel or a subgroup of
a mixer where the deliberate feedback signals
are not present .
Prior to making or changing any connections,
switch off the MFE-16M and the units to be con-
nected .
1) Connect the signal source (corresponding out-
put of a mixer, output of a microphone pre-
amplifier) to the jacks INPUT (13) . For a mono
signal, only connect the jack LEFT/ MONO and
engage the button MONO / STEREO (5) .
2) Connect the jacks OUTPUT (12) to the line in-
puts of the subsequent unit . When returning
the audio signal to a mixer, connect the jacks
OUTPUT to the corresponding return inputs,
to two input channels or to a stereo input
channel .
STEREO engaged), only connect one of the two
jacks OUTPUT, if required . The same signal is
present at these jacks .
3) Connect the low voltage plug of the power sup-
ply unit to the jack "9 V~" (11) and the power
supply unit to a mains socket (230 V/ 50 Hz) .
For the mono mode (button MONO /
9