APART PM7400 MKII User manual

PM7400 MKII
Instruction manual

Instruction manualPM7400MKII
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PM7400MKII Manual

4
Pre-amplifier
Safety first!
• Caution: hot and sharp surfaces! This professional device needs
to be installed by qualified personnel only.
• Please check the packing for any kind of damage upon
reception of the goods. If the packing is damaged, please
contact your dealer before opening it.
• !!!! Danger!!!! Exposure to high sound pressure levels may
cause permanent hearing loss. Hearing loss induced by
exposure to high sound pressure levels will vary from individual
to individual, but nearly everyone will lose some hearing
when exposed for a sufficient amount of time. Therefore it is
recommended that all persons exposed to equipment capable
of producing high sound pressure levels, such as this amplifier,
wear sufficient ear protection while installing or operating this
unit.
• Read all documentation before operating your equipment.
• Keep all documentation for future reference.
• Keep the carton and packing material, even if the equipment
has arrived in good condition.
• Should you ever need to send the unit back, use only the
original factory packing.
• Do not spill water or other liquids on or into the unit.
• Make sure power outlets conform to the power requirements
listed on the back of the unit.
• Do not use the unit if the electrical power cord is damaged.
• Always operate the unit with the AC ground wire connected to

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the electrical system ground.
• Turn the level controls on the amplifiers all the way down
during power-up to prevent speaker damage if there are high
signal levels at the inputs.
• Do not connect the inputs / outputs of amplifiers or consoles
to any other voltage source, such as batteries, mains sources or
power supplies, regardless of whether the amplifier or console
is turned ON or OFF.
• Power down and disconnect units from mains voltage before
making connections.
• Do not use the unit near stoves, heat registers, radiators, or
other heat producing devices.
• Do not operate equipment on a surface or in an environment
which may distort the normal flow of air around the unit. If the
unit is used in an extremely dusty or smoky environment, the
unit should regularly be “blown free” of dust.
• Do not remove the cover. Removing the cover will expose you
to potentially dangerous volt-ages.
• Do not drive the inputs with a signal level higher than that
which is required to drive equipment to full output.
• Do not run the output of any amplifier back into another input.
• In case of malfunction, this device should be serviced by
qualified service personnel only.

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Pre-amplifier
Features
How to mix music and microphone signals?
• 2 zone stereo mixer, 1 balanced line output and 1 unbalanced
line output with individual volume controls
• 6 line inputs, 1 balanced (XLR), 5 unbalanced (RCA)
• 2 balanced microphone inputs with switchable phantom power
• Switchable vox mute on mic 1 with adjustable music mute level
• Microphone priority contact
• 3 band tone control for line and mic inputs
• Toroidal power transformer
• Mono/stereo switch
• 19 inch rack mountable with fixed rack-ears
You can mix spoken microphone messages with music in different
ways.
1. Mix the microphone signals with the music by setting the mic
and line level volume controllers to an appropriate level. In order
to do this, the Vox/Ext. mute switch should not be pressed in and
the mute contact at the back should be open. You will notice
that you have to push the microphone level to a very high level.
This is not recommended.

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2. Mix the microphone signal of mic 1 with the music using the
‘vox’ or ‘voice-over’ circuitry: The Vox/Ext. mute switch must
be pressed in, and the mute contact at the back must be open.
By setting the mic 1 and vox mute level at the back to an
appropriate level, you can create an automatic music muting by
talking into mic 1. This is not valid for the mic 2 input, i.e. mic 2
signals can not activate the vox circuitry.
3. By closing the external mute contact at the back, you will mute
the music signal. Now you can speak into mic 1 or mic 2. The
muting circuitry will only mute the music signals and allow
the mic signals to pass through. This way you can create a
microphone priority system easily. Please note that the external
mute contact at the back can only be connected to a switch.
Never apply any voltages to the external mute contacts!

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Pre-amplifier
Front panel
1. Microphone 1 input: balanced jack input. This is the same input
as the microphone 1 combo XLR/ jack at the back. This mic has
a switchable vox circuit with adjustable music mute level. This
way, a spoken message will suppress the music. Alternatively,
you can use the priority contacts at the back. Closing the
contacts will mute the music. Phantom power is available.
Therefore you need to close the phantom power dipswitch at
the back of the unit. Phantom power is switched off by default.
Mic 1 will be heard in both output zones.
2. Mute mode switch: by pressing this switch in, the vox mode
is active on mic 1 only. The vox mute level can be set via a
potmeter on the back of the unit.
3. Mic 1 volume control: this volume control adjusts the mic 1
level.
4. Mic 2 volume control: this volume control adjusts the mic 2
level.
5. Microphone 2 input: balanced jack input. This is the same input
as the microphone 2 combo XLR/jack at the back. You can
use the priority contacts at the back to mute the music while
speaking. Closing the contacts will mute the music. Phantom
power is available. Therefore you need to close the phantom
power dipswitch at the back of the unit. Phantom power is
1
2
3 5
4 6 8
7
9 10 12 14 15 16
11 13

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switched off by default. Mic 2 will be heard in both output
zones.
6. Microphone bass tone control: for better speech intelligibility,
turn the microphone bass control down a little.
7. Microphone mid tone control: for better speech intelligibility,
turn the microphone mid control up a little if necessary. If you
experience feedback, turn the tone control down.
8. Microphone treble tone control: for better speech intelligibility,
turn the microphone treble control up a little if necessary. If you
experience feedback, turn the tone control down.
9. Power switch: flip the switch to power on/off the unit. The blue
LED lights up when the power is on.
10. Line inputs (music) bass tone control.
11. Line inputs (music) mid tone control.
12. Line inputs (music) treble tone control.
13. Line inputs (music) volume control. Normally, set this control
fully open. If you want to adjust the music level relative to the
microphone level, use this control. Caution: when the line input
volume control is set to the 0 position, no music will be heard.
14. Line input selector: turn this knob to select line inputs 1 to 6.
15. Zone 1 volume control: adjust the volume of zone 1. The green
leds light up when a sufficiently strong signal is present.
16. Zone 2 volume control: adjust the volume of zone 2. The green
leds light up when a sufficiently strong signal is present.

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Pre-amplifier
Rear panel
2 3 4 6 8
1 5 7 9
13 14 10 12 15 16 17
11
1. GND connection: connect an additional ground wire here if
necessary.
2. Line 1 balanced right channel input on XLR.
3. Line 1 balanced left channel input on XLR.
4. Line 2 unbalanced L/R input on RCA connectors.
5. Line 3 unbalanced L/R input on RCA connectors.
6. Line 4 unbalanced L/R input on RCA connectors.
7. Line 5 unbalanced L/R input on RCA connectors.
8. Line 6 unbalanced L/R input on RCA connectors.
9. Zone 1 unbalanced line output on RCA connectors.
10. Mono/stereo, GND lift and phantom power dipswitches. For
mono operation in both zones, flip dipswitch 1 to the on
position (down). Dipswitch 2 is normally to the on position: if
you want to separate the audio ground from safety ground, flip
this switch up. Dipswitch 3 and 4 activate the phantom power
for mic 2 or mic 1 when switched on.
11. External mute contacts: close these contacts to mute the music

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for microphone 1-2 priority. Do not apply any foreign voltage to
these connectors. Connect a potential free contact only!
12. Vox mute level control: turn this control to set the microphone
1 activated vox circuit mute level. This control has no function
when the front mute switch is not pressed to the in position.
13. Zone 2 right balanced right channel output on XLR.
14. Zone 2 left balanced left channel output on XLR.
15. Microphone 2 input: balanced XLR/jack combo input. This is
the same input as the microphone 2 jack at the front. You can
use the priority contacts at the back to mute the music while
speaking. Closing the contacts will mute the music.
16. Microphone 1 input: balanced XLR/jack combo input. This is the
same input as the microphone 1 jack at the front. This mic has
a switchable vox circuit with adjustable mute level. This way, a
spoken message will suppress the music. Alternatively, you can
use the priority contacts at the back (11). Closing the contacts
will mute the music.
17. Power cord receptacle with built in mains fuse: connect the
power cord here. Mains voltage is 230 VAC/50-60Hz. The
mains fuse is located inside this connector and can be reached
without opening the unit. When the fuse is broken, replace
only with a fuse of the same voltage and current rating. Fuse
rating: 315mAT/250V.

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Pre-amplifier
Technical Specifications
Inputs line level Balanced stereo inputs on XLR, 5 x
unbalanced stereo on RCA
Inputs mic level 2 X balanced on jack and combo
jack / XLR
Input sensitivity line inputs 500 mV
Input sensitivity mic inputs 5 mV
Input impedance line inputs 10 kΩ
Input impedance mic inputs 500 Ω
Phantom power supply Approx 15 V, switchable via
dipswitches for mic1 and mic2
Outputs Stereo unbalanced zone1 on RCA
stereo balanced zone2 on XLR
Output impedance <600 Ω
Nominal output level 1 V / 0 dBV
Liftable ground Yes, via dipswitch
Mono / stereo switch Yes, via dipswitch
S/N ratio line inputs >90 dB a weighted
S/N ratio mic inputs >70 dB a weighted
THD <0.1 %
Frequency response 20-25 kHz +0/-3 dB
Tone controls 80 Hz, 1.5 kHz, 10 kHz / up to
12 dB attenuation / boost
Channel separation >70 dB @ 1 kHz
Max power consumption 10 VA

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Mains operating voltage 230 VAC / 50-60 Hz
Fuse rating 315 mAt / 250 V
Dimensions 483 X 44 X 275 mm
(without rubber feet)
Net weight 2.6 kg

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Pre-amplifier
Note

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developed
by
Audioprof nv
Industriepark Brechtsebaan 8 bus 1
2900 Schoten - Belgium
Company names, product names and trademarks are property of their
respective owners.
v-Audio specifications are subject to change without notice.