®
AMV-7240 MKII
Automatic-Mixer/Amplifier
4
2. Setting/adjusting automatic mixing
•
After finishing input gain adjustment, please again insert the Jumper J14 for automatic mix function. Now only
the microphone with a direct input signal should switch on automatically (green LED ACTIVE). If more than the just
used microphone is active, please reduce slightly gain of the other microphones until you reach a proper treshold of
the gate. This should be repeated with each microphone. Lost input gain can be leveled by the master gain control.
3. Setting/adjusting volume
•
In normal operation the MIC/LINE potentiometers are set to maximum. Unused inputs are set to minimum.
For these inputs the AUTO OFF switch should be activated in order not to influence automatic mixing. The overall
volume is set with the rotary potentiometer VOLUME. Carefully observe onset of acoustical feedback.
In venues with high sound reflections (poorly damped) start with a setting of the knob to position 4. In instal-
lations with improved (higher damped) acoustical conditions the total useable volume may be increased –
but again: watch the danger of acoustical feedback.
4. AUX settings
Choose the input signal
AUX 1
or
AUX 2
by depressing the equivalent push button on the front panel (section
AUX
CONTROL
). The trimmers
GAIN AUX
lets you set the sensitivity so, that no limiting of the signal occurs (VOLUME 4),
verified by the
LIMIT
LED in the master section. Set the desired volume with the rotary knob
VOLUME
(on the front
panel in the section
AUX CONTROL
). The sound (tonal characteristics) can be set and optimised by the potentio-
meters
LOW
and
High
accordingly.
5. Ducking (automatic signal attenuation)
Connect the signal to the AUX input and set the trimmer
DUCK AMPL
to centre position. Now test this function by
speaking into the microphone at the
MIC/LINE
input. The
DUCK GATE
threshold may be adjusted at the same named
Trimmer, so that the AUX signal is attenuated to your preference. In its factory setting, a certain amount of ducking will
be noted. For church installations, we recommend to turn off the duck gate completely: just turn the potentiometer
complete clockwise.
6. Parametric equalizer
Factory setting of the parametric eq is OFF via Jumper J12. If you wish the equalizer, please reset the jumper to EQ
ON. The parametric equalizer is helpful for solving problems in venues with difficult acoustic environment and to
simultaniously optimise speech for maximum intelligibility. Feedback prone frequencies lowering the threshold for
onset of feedback are filtered out of the audio spectrum (reflected signals are time delayed). The EQ is simply acti
vated by
EQ
ON
. The built in equalizer covers the total audio spectrum. For ease of use the EQ is split into 4 overlap
ping sections: F1 = 20…9 00 Hz, F2 = 65…3 000 Hz, F3 = 170…7 000 Hz and F4 = 450…20 000 Hz. The (critical) fre
quency is selected by the trimmer
FREQ
, the bandwidth Q = 1…12 with the trimmer
BAND
and the amplitude range
with the trimmer
GAIN
. The sections are overlapping in order to filter out a relative small and steep frequency range
(notch-filter).
7. Amplifier output level
When setting up the system in venues with high acoustical damping factor, where high output power can be utilized,
set the rotary pot
VOLUME
in the MASTER area on the front panel so, that no permanent limiting of the output signal
occur (watch the LIMIT LED, which also can indicate amplifier overload).
