PA Power Amplifier
Please read these instructions carefully prior to
operation and keep them for later reference .
All operating elements and connections de-
scribed can be found on the fold-out page 3 .
Connection of the speakers (chapter
4 .1) requires adequate technical knowledge
in 100 V PA technology and is to be made
by experts only . Operation of the amplifier
is easy, even for adults without any expert
knowledge . However, in case of any queries,
please contact your installer or retailer .
1 Operating Elements
and Connections
1.1 Front panel
1 Level control
2 Level LEDs, in case of overload the red
LED CLIP lights up
3 Operating LED PWR
4 LED PROT lights up in case of activated
pro tective circuit:
1 . for approx . 1 second after switching
on (switch-on delay)
2 . for approx . 1 second after switching off
3 . in case of overload of the amplifier
4 . in case of overheating of the amplifier
5 Overheating LED TEMP lights up when the
heat sink temperature reaches 100 °C . In
this case, the amplifier is muted . The red
LED PROT (4) lights up additionally .
6 On / off switch POWER
Note: If a 24 V voltage from an emer-
gency power unit is present at the termi-
nals DC POWER (7), the amplifier cannot
be switched off .
1.2 Rear panel
7 Screw connections for an emergency
power supply (24 V⎓)
8 Jack for the supplied mains cable for con-
nection to 230 V/ 50 Hz
9 Speaker connections
10 Connection for 100 V monitor speakers
for monitoring purposes
Important! These terminals are con-
nected in parallel to those for 100 V
speakers (COM and 100 V) . Do not over-
load the amplifier . To calculate the total
load, the load by a monitor speaker must
be added to the load by the other main
speakers .
11 Protective cover for the speaker connec-
tions
WARNING Never use the amplifier
without the cover .Other-
wise, when touching the
connections, there is the
hazard of an electric shock .
12 On / off switch 400 Hz for the high-pass
filter (for bass attenuation)
6
13 Signal input via the balanced XLR jack;
sensi tivity for optimum level control
+4 dBu (1 .2 V)
14 Feed-through output via the XLR jack for
con nection of a further PA amplifier
15 Balanced signal input via screw connec-
tions; sensitivity for optimum level control
+4 dBu (1 .2 V)
16 Feed-through output via screw connec-
tions for con nection of a further PA am-
plifier
2 Safety Notes
This unit corresponds to all relevant directives
of the EU and is therefore marked with
WARNING The unit is supplied with haz-
ardous mains voltage . Leave
ser vicing to skilled personnel
only and do not insert anything
through the vents! Inexpert handling or
modification of the unit may cause an elec-
tric shock hazard .
During operation there is a hazard of con-
tact at the speaker connections (9, 10) with
a voltage of up to 100 V . Never use the am-
plifier without protective cover (11) .
Make or change all connections only with
the PA system switched off .
•
The unit is suitable for indoor use only . Pro-
tect it against dripping water and splash
water, high air humidity, and heat (admis-
sible ambient temperature range 0 – 40 °C) .
•
Do not place any vessels filled with liquid,
e . g . drinking glasses, on the unit .
•
The heat being generated in the unit must
be carried off by air circulation . Therefore,
the air vents at the housing must not be
covered .
•
Do not set the unit into operation, or im-
mediately disconnect the mains plug from
the mains socket if
1 . there is visible damage to the unit or to
the mains cable,
2 . a defect might have occurred after a drop
or similar accident,
3 . malfunctions occur .
The unit must in any case be repaired by
skilled personnel .
•
Never pull the mains cable to disconnect
the mains plug from the mains socket, al-
ways seize the plug .
•
For cleaning only use a dry, soft cloth, by
no means chemicals or water .
•
No guarantee claims for the unit and no li-
ability for any resulting personal damage or
material damage will be accepted if the unit
is used for other purposes than originally
intended, if it is not correctly connected,
operated, or not repaired in an expert way .
If the unit is to be put out of oper-
ation definitively, take it to a local
recycling plant for a disposal which
is not harmful to the environment .
3 Placing the Amplifier
The amplifier is designed for insertion into a
rack (482 mm /19") but it can also be used
as a table top unit . In any case, air must be
allowed to pass through all air vents to ensure
a sufficient cooling of the power amplifiers .
3.1 Rack installation
rack spaces (= 89 mm) are required for rack
installation . To prevent top-heaviness of the
rack, the amplifier must be inserted into the
lower part of the rack . For a safe fixing the
front panel alone is not sufficient . The ampli-
fier must additionally be screwed to the rack
by means of the rear mounting straps .
.
The heated air blown out from the am-
plifier must be allowed to leave the rack rear-
wards or upwards . Otherwise the heat accu-
mulation in the rack may not only damage
the amplifier but other units as well . In case
of insufficient heat dissipation, insert a ven-
tilation unit into the rack above the amplifier .
4 Connecting the Amplifier
All connections should only be made by
skilled personnel and by any means with the
amplifier switched off!
4.1 Speakers
The connections for the speak ers are below
the protective cover (11) . For connection
screw off the cover .
WARNING The amplifier must not be
operated without the protec-
tive cover (11) . During oper-
ation there are hazardous
voltages of up to 100 V at the speaker con-
nections (9, 10) . After connect ing, tightly
screw the cover again so that the contacts
are protected against touching .
PA speakers (fig . 3 and 4) or 8 Ω speakers
or speak er groups with a total impedance of
at least 8 Ω (figs . 5 to 8) can be connected .
4.1.1 PA speakers and monitor speakers
Caution! In case of PA speakers (figs . 3 and 4)
the total load by the speakers must
not exceed
240 W RMS (PA-1242)
480 W RMS (PA-1480),
otherwise the amplifier may be
damaged by overload . 100 V mon-
itor speakers [connected to the
terminals MONITOR (10)] must be
taken into account .
Connect the speakers to the corresponding
speaker terminals (9) . Observe the correct
polarity (positive and negative connections
as shown in figs . 3 and 4) . The positive con-
nection of the speaker cables is always spe-
cially marked . It is possible to connect a 100 V
monitor speaker to the terminals MONITOR
(10) for monitoring purposes . The terminals
MONITOR are connected in parallel to the
terminals COM and 100 V .