IMG STAGELINE STA-225 Bedienungsanleitung Seite 7

Stereo PA Amplifier
These instructions are intended for users
without any specific technical knowledge .
The speakers, however, should only be con-
nected by persons with the corresponding
technical knowledge . Please read these in-
structions carefully prior to operating the unit
and keep them for later reference .
All operating elements and connections
described can be found on the fold-out
page 3 .
Contents
1 Operating Elements and
Connections . . . . . . . . . . . . . 7
1 .1 Front panel . . . . . . . . . . . . . . 7
1 .2 Rear panel . . . . . . . . . . . . . . 7
1 .3 Display . . . . . . . . . . . . . . . . 7
2 Safety Notes . . . . . . . . . . . . 8
3 Applications . . . . . . . . . . . . . 8
4 Setting up the Amplifier . . . . . . 8
4 .1 Rack installation . . . . . . . . . . . 8
5 Connections . . . . . . . . . . . . . 8
5 .1 Inputs . . . . . . . . . . . . . . . . 8
5 .2 Speakers . . . . . . . . . . . . . . . 8
5 .3 Power supply . . . . . . . . . . . . . 8
6 Operation . . . . . . . . . . . . . . 9
6 .1 Selecting the operating mode . . . . 9
6 .2 Switching on / off . . . . . . . . . . . 9
6 .3 Adjusting the level . . . . . . . . . . 9
6 .4 Power indication . . . . . . . . . . . 9
6 .5 Groundlift switch . . . . . . . . . . . 9
7 Protective Circuits . . . . . . . . . 9
8 Specifications . . . . . . . . . . . . 9
1 Operating Elements and
Connections
1.1 Front panel
1 Volume controls
one each for the channels L-CH and R-CH
Note: In bridge mode, the control of the
channel R-CH has no function .
2 Status LEDs
one each for the channels L-CH and R-CH
PROTECT
lights up when the protective circuit sepa-
rates the speaker from the amplifier: for a
short time after switching-on and in case
of overload /overheating of the amplifier
LIMITER
lights up when the limiter circuit is active
and reduces the signal to prevent over-
load
SIGNAL / −20 dB / −10 dB
indicate the level of the output signal
3 LC display to show the operating para-
meters and status ( ☞ chapter 1 .3)
4 Button LOAD 4/ 8 OHM to select the
speaker load for the correct calculation
of the power indication on the display (3)
(if required, press several times)
5 Mains switch POWER
1.2 Rear panel
6 Inputs as XLR jacks
each for the channels L-CH and R-CH
Note: In bridge mode, the input of chan-
nel R-CH has no function .
7 Inputs as 6 .3 mm jacks, balanced, for con-
nection of a signal source with line level,
one each for the channels L-CH and R-CH,
alternatively to the XLR jack (6)
Note: In bridge mode, the input of the
channel R-CH has no function .
8 Switch GROUNDLIFT to separate the sig-
nal ground from the housing ground:
GROUND
signal ground and housing ground are
connected
LIFT
signal ground and housing ground are
separated (groundlift)
9 Switch MODE for selection of the oper-
ating mode STEREO / BRIDGE
( chapter 6 .1)
☞
10 ON / OFF switch LIMITER for the automatic
level limitation
11 Speaker outputs as screw terminals, alter-
natively to the speaker jacks (12 and 13)
12 Speaker jack R-CH
13 Speaker jack L-CH
14 Speaker jack BRIDGE for bridge mode
15 Mains jack for connection to a socket
(230 V/ 50 Hz) via the supplied mains cable
16 Support for the mains fuse;
only replace a blown fuse by one of the
same type
1.3 Display
Standard indication during operation (fig . 3)
a output power of both outputs, calculated
according to the output voltage measured
and the load impedance selected [button
LOAD 4 / 8 OHM (4)]
Note: The calculation is not effective in
bridge mode .
b for both outputs;
CLIP ON / OFF
if is shown, the amplifier input
CLIP ON
is overloaded . In this case, reduce the input
level with the corresponding control (1) .
c PROT ON / OFF (= PROTECTION,
☞ chapter 1 .1, item 2, status LED PROTECT)
d temperature at the power transistors of
both channels
e vertical bargraph indication for the output
signals of both channels
Indication for a few seconds after actuating
a volume control (1), the switch LIMITER (10)
or the switch MODE (9) (fig . 4)
f of the selected op-
STEREO / BRIDGE
erating mode
g Status indication for the switch LIMITER (10)
= limiter switched on
LIMT ON
LIMT OFF = limiter switched off
h ATTEN for attenuation of the input signals
shows the position of the volume controls
(1) numerically (i) and as a vertical bar (j)
Indication for a few seconds after actuating
the button LOAD 4 / 8 OHM (4) (fig . 5)
k selected load impedance for the calculation
of the output power shown (a)
7