MIXING AMPLIFIERS
MIXING AMPLIFIERS
25. Rec. out
When you need a copy of the total mix, you can connect this output to any recording device such as tape
deck, MD recorder, VHS recorder, etc….You can also use this output to feed an extra amplifier. This output level
cannot be controlled separately. When you connect your
MA125
pre-amp out or record out to a microphone input of
another mixing amplifier, this input will have signal overload and the sound will be masked. In this case you should
use a line input, a DI-box or other signal levelling device. Never connect this output to an amplifier loudspeaker
output!
26. CD input (300mV)
Use these stereo RCA inputs to connect a line level source such as CD players, MD players,
etc…. You have to make your choice with the selector at the front (see 10). Stereo signals will be summed together
to mono.
27. TUNER input (500mV)
Use these stereo RCA inputs to connect a line level source such as a TUNER
You have to make your choice with the selector at the front (see 10). Stereo signals will be summed together to
mono.
28. Line 4 / Mic4 input
Use only one of these parallel wired inputs at the time! To the XLR3 balanced input you can
connect any microphone using a balanced, two wire shielded, cable. (1=earth / 2 =hot / 3=cold). For using condenser
microphones see 32. The Microphone 4 input is a XLR3 jack, which will accept a normal XLR3 male plug.
Line 4 is more sensitive than the other line (music) inputs, therefore ideal to connect wireless microphone receivers.
29. Mic 2, 3 & Mic 4 XLR + jack input
To the XLR, or parallel wired stereo jack, balanced input you can connect any
microphone using a balanced, two wire shielded, cable. (1 or sleeve = earth / 2 or tip = hot / 3 or ring = cold). For
using condenser microphones see 32.
30. Mic 1 XLR / DIN5 / Euro block
Use max. two of these parallel wired balanced inputs at the time! See wiring
diagram at the back. These three inputs have been wired in parallel with the balanced jack input at the front. When
you use the APart MICPAT or MICPACB paging microphones, connected directly to the DIN5 input, the signals fed into
the line inputs are muted automatically while paging. The same kind of connection can be made using the euro block
connector. To use “vox mute” see 30.
Phantom power to use condenser microphones see 33
31. Vox mutes all
When you activate “vox mute” by turning this trimmer clockwise to the desired threshold level, the
signal of any Mic1 input has priority over all other inputs (except emergency). When you don't need “vox mute”, turn
this trimmer fully counter-clockwise to the “OFF” position.
32. Airflow output
This airflow output should be kept free at all times !
Keep sufficient room on top and the two sides of your MA125.
33. Phantom on/off
When you switch to the ON position, phantom power will be supplied to the microphone input
involved, so you can use condenser microphones. In this case
NO
unbalanced jacks should be used! Phantom
power does not damage dynamic balanced microphones.
4
3
MA125 inside controls
Inside settings should only be done by persons familiar to electrical equipment!
Power supply fuse (inside the housing)
When this fuse blows, replace it by the same type: 15A quick blow. When this happens frequently, contact your
nearest dealer.
Now you are ready to build your solid sound system and
our extra features will be of great help
.
Note:
In our policy of continuous improvement, changes can appear without prior notice, including the user manual.
14. Voltage selector
Set the local voltage. If any doubt, contact your dealer. The unit is shipped with the selector
set to 230VAC.
15. Mains socket
The unit can be connected to the mains circuit by a standard IEC type power cord. This socket
contains a 2,5AT, slow blow fuse. Use a screw driver to flip out the fuse compartment and to replace it by the same
type. When this fuse blows frequently you should check the speaker load or bring the
MA125
to a qualified service
centre. First check whether you didn't use a quick-blow fuse!
16. Emergency power supply
You can power the amplifier directly from an emergency battery or power supply
supplying 24V DC/15A.
17. Loudspeaker outputs
For low impedance use com and 8? . Keep impedance above 8 ? .
For 50, 70 or 100V speaker lines use COM and 50, 70 or 100V terminals.
For 100V operation, the total minimum impedance of the loudspeaker lines should be 80 ? . For 70V operation the
minimum impedance should be 40 ? and for 50V 20 ohm.
Don't mix the types of speaker connections. Only one at the time should be used, unless you are able to calculate a
combination which does not overcharge the amplifier (example: 160? at 100V for a loud zone in combination with 40?
at 50V for a quiet zone).
18.
24V DC output
At this terminals (-/+) 24V DC will be available (max. 0,6A) from the moment any priority has been
activated, to control priority relays of local volume attenuators or other devices.
19. Emergency / telephone level
With this potentiometer you can set the desired level of the line level signal
inserted into the priority signal input 20. This level will not be influenced by the “master” level.
20. Emergency / telephone input
Here you can feed the audio source for paging emergency messages, etc.. This
input, at line level, has automatic activation above 200mV and has a line transformer to avoid ground loops (useful for
telephone). Please use a balanced, shielded line cable. Connect the HOT signal to +, the COLD to - and the shield to
G (when connecting the shield only at the MA125 side, you might avoid a ground loop, which creates hum and buzz).
This signal is directly fed into the main amplifier.
No microphones should be connected directly to this input without using a mic to line pre-amplifier.
21. Priority over music contact
By closing the contact of the euro block connector or pins 4 and 5 of the DIN5
connector, the signal of microphones 1 to 4 have priority over the music sources (TUNER, CD and AUX). So, the
contact closure of the contacts mentioned can give priority to the other microphone inputs as well. At the same time
24 V DC will be available at terminal 18. This is very useful when using several microphones in supermarkets, etc…
22. Chime level
When one of the priority contacts are closed a chime can be activated by turning this trimmer
clockwise to the desired chime level. When you don't need a chime, turn this control fully counter-clockwise to the
“OFF” position.
23. Power amp in / pre amp out
You can send the signal of the pre-amplifier to an external device such as an
equalizer (APart PXQ2215) or processor and feed the treated signal back into the amplifier via the power amp input.
From the ”pre-amplifier out” you can also feed extra power amplifiers such as the APart PA240P. When you don't use
this feature, the RCA bridge should be placed.
24. Aux. mono
Here you can feed the signal of an external mono music source.
Back panel
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