Manual-7
OPERATING INSTRUCTIONS
INITIAL OPERATION
Operation of the MP 24x is fairly straightforward,
deviating only slightly from other products of its type.
Assuming at least one turntable is connected and assigned to
PHONO 1, operation consists of the following: Make sure all
faders are set to zero, the MIC, LOOP, EQ, and ACTIVE
CROSSFADER are all
disengaged
, (switches
out
) and that all
rotary LEVEL controls are either fully CCW or in their center
detents, whichever applies. Select PHONO l on Input Channel
1. Simultaneously raise the Channel 1 fader and the MASTER
LEVEL fader. Before much travel is reached on the faders,
the results should be heard. If not, shut everything down and
recheck connections, power to the mixer (look for the yellow
POWER light) and ancillary devices (EQs, crossovers,
amplifiers, etc.)
Once an output is established from the turntable, go ahead
and try everything else. Assign all Inputs to the Channels they
will be used, and test the system. Once all sources are set as
desired, proceed.
REAR PANEL ADJUSTMENTS
There are some controls on the rear panel which need to
be set. Set the METER SENSITIVITY ADJUST so the
system is at maximum level, (usually just short of amplifier
clipping). Run the system up to this maximum level and turn
the METER SENSITIVITY ADJUST so that the highest
peaks on the PEAK PROGRAM METER occasionally hit the
+8 dB indicator. This warns the operator that further pressure
on the throttle will overdrive the system.
At this point check the MAXIMUM OUTPUT GAIN
REDUCTION control so that with the MASTER LEVEL at
“10”, the meter responds as it did in the previous step. This
would be a good time to make the adjustment. This may be
accomplished by turning the rear panel MAX OUTPUT
GAIN REDUCTION adjustment all the way down, pushing
the MASTER LEVEL fader all the way up, setting a normal
mix level on the Input fader, and then turning up the MAX
OUTPUT GAIN REDUCTION adjustment on the rear until
the required output level is attained. In some cases, make this
adjustment with both the Source Level and the MASTER
LEVEL faders all the way up. This is acceptable only if
sources can be adjusted such that they all have equal output
before they reach the Input of the MP 24x. If this is not
possible, full system drive will not come from some compo-
nents. To accomplish this feat, identical cartridges in all
turntables are required so the phono levels are all the same.
Having done all of this it is possible to use the MAX OUT-
PUT GAIN REDUCTION on all of your sources.
The other rear panel adjustment that should be made at
this time has to do with the maximum deviation to the
frequency response of the system left to the operator. This is
controlled by the EQ RANGE switch. In the
out
position, the
range of all of the EQ controls is ±8 dB. In the
in
position,
this range is reduced to ±4 dB. The latter is considered safer
in situations where taste makes waste—in drivers, that is.
THE HEADPHONE CONTROL (CUE) SYSTEM
To use the HEADPHONE CUE System, signal must be
present at one of the Inputs. (Well, at least you do to make
sure it works.) Depressing the CUE switch for the respective
Input Channel presents this signal to the Headphone Cue
amplifier. An LED illuminates next to the CUE switch,
attesting to the fact that it was indeed pushed
down
. Now
select
how
to listen to it — Mono
Cue
in one ear, Mono
Program
in the other,
Stereo Program
in both ears, or
Stereo
Cue
in both ears. The STEREO/MONO CUE switch allows
this flexibility. To vary the level between Cue and Program,
rotate the HEADPHONE PAN control in the desired direc-
tion. CCW rotation increases the Cue Level, CW rotation
increases the Program Level. The overall volume of all of this
is then controlled by the rotary HEADPHONE LEVEL
control.
USING THE ASSIGNABLE ACTIVE CROSSFADER
Active Crossfader™
technology combines state of the art
voltage controlled amplifier design with a professional
quality, dual-rail Alps crossfader control. This combination
sets new standards for performance, reliability and service-
ability. Virtually all crossfader noise is eliminated. Channel to
channel crosstalk is greatly reduced and the
off
isolation of
the faded channel is greatly increased.
Active Crossfader
technology dramatically increases the service life of the
crossfader. In the unlikely event of crossfader failure, there is
no loss of signal. If a crossfader becomes rough or noisy, it
may be “hot-swapped” during a performance
with no inter-
ruption of the audio signal
. Simply use the input faders to set
the audio levels while the crossfader is out of service.
For normal operation, press the Crossfade ENGAGE
switch. The green LED next to the switch illuminates. The
Crossfade ASSIGN switches determine the two Input Chan-
nels that are mixed by the Crossfader. As an example, assume
the left ASSIGN switch is set on 1 and the right ASSIGN
switch is on 2. This activates both mix faders on Channels 1
and 2. Their outputs, however, are under the control of the
Crossfader. When in its left-most position, only Channel 1
appears at the Outputs. Both Channels are present in equal
levels in the when the Crossfader is brought to the middle,
and only Channel 2 is heard once the far right is reached.
Note that the sound pressure level does not change as this
transition is effected. This is a constant power Crossfader,
meaning that if the two input signals are equal, a steady
volume level is maintained no matter where the Crossfader is
positioned. This, of course, gets a bit sticky to predict when
one song may be in fade-out as the operator crossfades from
one to the next which is building in volume.
Once crossfaded to Channel 2, maybe cue up some video
and put the audio on Channel 4. Hard to do? No way. Simply
pull the Channel 1 fader to zero, set the ASSIGN switch on
the left of the Crossfader to Channel 4, Cue up 4, set the level
on fader 4 and Crossfade into it. We realize that it’s a bit
strange to Crossfade from 2 to 4 by sliding the fader to the
left, however it’s just an unavoidable oddity caused by having
so much flexibility.
