Operating Elements And Connections; Safety Notes; Connecting The Amplifier - IMG STAGE LINE STA-1000 Instruction Manual

PA Stereo Amplifier
These instructions are intended for users without
any specific technical knowledge . The speakers,
however, should only be connected by persons
with the corresponding technical knowledge .
Please read these instructions 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 .
1 Operating Elements and
Connections
1.1 Front panel
1 Volume control for the left channel L-CH
2 Status LEDs for the left channel:
PROTECT lights up with activated protective
circuit (the connection to the speakers is
separated):
1 . after switching-on for a short time
2 . in case of overload/overheating (e . g . also
by short circuit at the output)
3 . in case of DC voltage at the output
LIMITER lights up when the input signal is
too high and limited by the limiter
ACTIVE lights up as a power indication
−25 dB, −20 dB, −15 dB show the input
level
3 LC display for operating mode and temper-
atures
4 Status LEDs for the right channel (
5 Volume control for the right channel R-CH
6 POWER switch
1.2 Rear panel
7 Balanced inputs: XLR jacks for the left chan-
nel (L-CH) and the right channel (R-CH)
8 Balanced inputs: 6 .3 mm jacks for the left
channel (L-CH) and the right channel (R-CH)
9 DIP switches for selecting the operating
mode and for separating signal ground and
housing ground:
operating mode STEREO
operating mode PARALLEL
operating mode BRIDGE
signal ground connected to
housing ground
signal ground and
housing ground separated
(groundlift)
10 Switch FILTER with three positions
SUBWOOFER: low pass filter
with −6 dB at 120 Hz
SATELLITE: high pass filter
with −6 dB at 120 Hz
FULLRANGE: no filter
11 Speaker output: Speakon jack, depending
on plug configuration for the left channel,
the right channel, or for bridge mode
12 Speaker output: Speakon jack for the right
channel
13 Speaker outputs: screw terminals
14 Only for models STA-600 and STA-1000:
Support for the mains fuse
6
Replace a blown fuse by one of the same
type only .
15 Only for model STA-1400:
Protective switch to protect the unit; to reset
the released switch, press down the button
16 Mains jack for connection to a socket
(230 V/ 50 Hz) via the supplied mains cable
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 ser-
vicing to skilled personnel only
and do not insert anything into
the air vents! Inexpert handling may result in
electric shock! .
There is a hazard of contact at the speaker
connections with a dangerous voltage during
operation . All connections must only be made
or changed with the unit switched off .
•
The unit is suitable for indoor use only . Pro-
tect it against dripping water and splash
water, high air humidity, and heat (admissible
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 off by air circulation . Therefore, the
air vents at the housing must not be covered .
item 2)
☞
•
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, always
seize the plug .
•
For cleaning only use a dry, soft cloth, never
use chemicals or water .
•
No guarantee claims for the unit and no liabil-
ity for any resulting personal damage or mate-
rial damage will be accepted if the unit is used
for other purposes than originally intended, if
it is not correctly connected or operated, or if
it is not repaired in an expert way .
If the unit is to be put out of operation
definitively, take it to a local recycling
plant for a disposal which will not be
harmful to the environment .
3 Applications
This PA stereo amplifier has especially been
designed for stage and disco applications . The
amplifier may be operated in stereo mode, in
mono parallel mode, or in mono bridge mode .
Due to a switchable filter, the amplifier may
also be used only for subwoofers or only for
the frequency range exceeding 120 Hz . Extensive
protective circuits protect the amplifier and the
speakers connected . Two powerful, tempera-
ture-controlled fans supply the necessary cooling
of the amplifier .
4 Setting-Up
The amplifier is provided for installation into a
rack (482 mm / 19"), but it may also be used as a
table top unit . In each case air must be allowed
to flow freely through all ventilation vents so
that a sufficient cooling is ensured .
4.1 Rack installation
For rack mounting, 2 RS (rack spaces) = 89 mm
are required . The heated air blown out by the
amplifier at the rear must be able to dissipate
from the rack, otherwise a heat accumulation
.
will occur in the rack which may not only dam-
age the amplifier but also other units in the rack .
In case the heat is not dissipated sufficiently, a
fan unit has to be inserted 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 bottom plate .
5

Connecting the Amplifier

All connections must only be made or changed
with the unit switched off!
5.1 Inputs
Connect the output of a preamplifier or mixer
to the XLR jacks or 6 .3 mm jacks INPUTS (7, 8) .
Both jacks are designed for balanced signals; the
pin configuration is shown in fig . 2 . However,
also sources with unbalanced signals may be
connected . For this purpose, the connection to
the 6 .3 mm jacks can easily be made via 2-pole
6 .3 mm plugs .
– The input signal should have line level . For
rated power of the amplifier, an input signal
of 1 V is required as a minimum .
– For bridge mode or parallel mode, only con-
nect the input of the left channel L-CH .
– The XLR jack (7) is in each case directly con-
nected to the 6 .3 mm jack (8) of the same
channel . Thus, when connecting the signal
source to a jack, the signal of the other jack
can be picked up to feed it e . g . to an addi-
tional amplifier .
5.2 Speakers
The maximum output power is reached in stereo
mode and in parallel 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
decrease . In bridge mode, the maximum out-
put power will be reached with an 8 Ω speaker
(minimum admissible load impedance in bridge
mode) . The required power rating (P
speakers is listed in the table fig . 3 .
Connect the speakers to the Speakon jacks
(11, 12), pin configuration of the plug see fig . 2,
or to the screw terminals (13) . When connecting
the speakers, pay attention to the same polarity
of all speakers .
After connecting a Speakon plug to the jack,
turn it clockwise until it locks . For removing it
later, retract the lock latch at the plug and turn
the plug counter-clockwise .
If the screw terminals are used, ensure that
the cable ends are not stripped too far and that
no bare wires protrude (hazard of contact and
short circuit) .
The Speakon jack of the output L-CH (11) is
additionally provided with the signals of the right
) of the
min