Safety Notes; Applications; Setting Up The Amplifier; Rack Installation - IMG STAGELINE STA-225 Mode D'emploi

2 Safety Notes

The 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
servicing to skilled personnel
only and do not insert any-
thing into the air vents! In-
expert handling may result in
electric shock .
•
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 dissipated by air circulation . Never cover
the air vents of the housing .
•
Do not set the unit into operation, and 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, never
use chemicals or water .
•
No guarantee claims for the unit and no
liability for any resulting personal damage
or material damage will be accepted if the
unit is used for other purposes than orig-
inally intended, if it is not correctly con-
nected or operated, or if it is 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
will not be harmful to the environ-
ment .

3 Applications

This stereo PA amplifier is especially designed
for applications on stage and in discotheques .
It can be used in stereo mode or in mono
bridge mode . Extensive protective circuits pro-
tect the amplifier and the speakers connected .
Two powerful, temperature-controlled fans
provide the necessary cooling of the amplifier .
8

4 Setting up the Amplifier

The amplifier is provided for insertion into a
.
rack for units with a width of 482 mm (19"),
but it can also be used as a tabletop unit . In
each case, air must be allowed to flow freely
through all air vents to ensure sufficient cool-
ing of the amplifier .

4.1 Rack installation

For rack mounting, 2 RS (rack spaces) = 89 mm
are required . Above the amplifier, one rack
space should be left unused for air supply . The
heated air blown out by the amplifier to the
rear and to the sides must be able to dissipate
from the rack, otherwise heat will accumulate
in the rack which may not only damage the
amplifier but also other units in the rack . In
case of insufficient heat dissipation, insert a
fan unit into the rack .
To prevent top-heaviness of the rack, the
amplifier must be inserted in the lower part
of the rack . To ensure a safe fixing, the front
panel alone is not sufficient . In addition, the
unit must be fastened at the rear side or be
supported by means of lateral rails or a bot-
tom plate .
5 Connections
Prior to connecting units or changing existing
connections, switch off the amplifier and the
units to be connected .

5.1 Inputs

Connect the output of a preamplifier or a
mixer to the 6 .3 mm jacks INPUTS (7) or the
XLR jacks (6) .
– The jacks are designed for balanced signals;
the pin configuration is shown in fig . 2 . For
connection of sources with unbalanced sig-
nals, 2-pole 6 .3 mm plugs may be used or
adapters with the XLR contacts 1 and 3
bridged .
– The input signal should have line level . For
rated power of the amplifier, an input signal
of 1 .3 V is required as a minimum .
– For bridge mode, only connect the input of
the left channel L-CH .
– As the XLR jacks and the 6 .3 mm jacks of
the same input are directly connected, they
can also be used for passing on the signal
e . g . to an additional amplifier .

5.2 Speakers

The maximum output power is reached in
stereo mode when connecting 4 Ω speakers
(minimum admissible load impedance) . It is
also possible to connect 8 Ω speakers, how-
ever, in this case the output power will slightly
be decreased . In bridge mode, the maximum
output power will be reached with an 8 Ω
speaker (minimum admissible load imped-
ance in bridge mode) . The required power
rating (P ) of the speakers is listed in the
min
table fig . 6 .
For stereo mode, connect the speakers to the
speaker jacks (12, 13), pin configuration of the
plug see fig . 2, or to the screw terminals (11) .
– After inserting a speaker plug into the jack,
turn the plug clockwise until it engages . To
remove the plug, retract the latch lock at
the plug and turn the plug counter-clock-
wise .
– If the screw terminals are used, ensure that
the cable ends are not stripped too far and
that no bare wires protrude (hazard of con-
tact and short circuit) .
– When connecting the speakers, make sure
that all speakers have the same polarity .
For bridge mode, connect the positive pole
of the speaker to the positive terminal (11)
of the left output L-CH and the negative pole
of the speaker to the positive terminal of the
right output R-CH (11) . (By signal inversion in
bridge mode, the positive terminal of the right
output becomes the negative connection for
the speaker .) The speaker can alternatively
also be connected to the speaker jack BRIDGE
(14) [pin configuration of the plug
Table fig . 6 also shows possibilities of con-
nection for several speakers to one output .
For each speaker, the minimum power rating
(P ) with the corresponding impedance (Z)
min
is listed . When interconnecting several speak-
ers, special attention has to be paid to the
correct connection of the positive and neg-
ative terminals .
Important: The total impedance at each out-
put must not fall below 4 Ω in stereo mode
and must not fall below 8 Ω in bridge mode!

5.3 Power supply

Connect the mains cable to the mains jack (15)
and the mains plug to a socket (230 V/ 50 Hz) .
fig . 2] .
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