LD Systems IPA 412 T Bedienungsanleitung Seite 6

INPUT SECTION
8
ON DIP
1 2 3 4
IN1 - IN4
4
Two 6-pole terminal block connections for input channels 1 and 2 or 3 and 4. Pins +, - and G form the balanced line input of the corresponding
channel; suitable terminal blocks are included in the packaging.
BRG / ST / PAR
5
ON DIP
3-way switch to adjust the channel mode.
1 2 3 4
BRG (Bridge mode): The power amplifiers of channels 1 and 2 or 3 and 4 are combined to provide more powerful mono power amplifiers. If the
bridge mode is activated for channels 1 and 2, IN1 serves as a line input, and the volume is set using level control CH1. Line input IN2 and level control
CH2 are deactivated. If the bridge mode is activated for channels 3 and 4, IN3 serves as a line input, and the volume is set using level control CH3.
Line input IN4 and level control CH4 are deactivated.
Bridge operation is only available to drive low-impedance loudspeakers. When wiring the cables, ensure that the power amplifiers are correctly
assigned and that the impedance of the connected loudspeaker or loudspeaker system is at least 8 Ohm!
The configuration for channel 1/2 in bridge operation is: CH1 4OHM = positive pole, CH2 4OHM = negative pole.
The configuration for channel 3/4 in bridge operation is: CH3 4OHM = positive pole, CH4 4OHM = negative pole.
Caution: For safety reasons, bridge mode BRG and HI-Z mode cannot be activated at the same time. As soon as the 3-way switch is set to BRG and
the corresponding DIP switch to HI-Z, an internal switching process prevents both operating modes from activating simultaneously. HI-Z mode has
priority and is activated, while BRG bridge mode remains deactivated or is disabled. This state is signaled by the corresponding display field BRIDGE
(No. 21) on the front panel flashing fast.
ST (stereo mode): In stereo mode, each individual line input is assigned to the corresponding speaker output, which means a signal that is present
at line input IN1 is routed to speaker output CH1 and a signal that is present at line input IN2 is routed to speaker output CH2. The same also applies
to channels 3 and 4. The corresponding level controls work independently of each other.
PAR (Parallel Mode): In parallel mode, a signal present at line input IN1 is routed to speaker outputs CH1 and CH2, while line input IN2 is deactivated.
Level controls CH1 and CH2 are used to separately set the volume for the corresponding amplifier channel. A signal present at line input IN3 is
routed to speaker outputs CH3 and CH4, while line input IN4 is deactivated. Level controls CH3 and CH4 are used to set the volume separately for the
corresponding amplifier channel.
6 CLIP IN1 - IN4
The clip LED of the corresponding channel is lit when the level of the input signal reaches -1dBFS and the channel is therefore operated at the
distortion limit. Reduce the output level of the corresponding source device to avoid signal distortion.
7 LEVEL CONTROL CH1 - CH4
Level control for the individual adjustment of the volume of speaker outputs CH1 to CH4 in stereo and parallel channel modes. As soon as the bridge
mode (BRG) is activated, the level controls CH2 and CH4 have no function.
8 REMOTE IN / OUT
RJ45 connections for LD Systems REMOTE bus accessories. The accessories are connected in series to the REMOTE IN. An RJ45 bus terminating plug is
included in the package. This should be connected to REMOTE OUT as standard and, under normal circumstances, not be removed from this socket.
An RJ45 bus terminating plug should also be connected to the REMOTE IN of the last REMOTE bus accessory in the chain of accessory devices.
For more information on the REMOTE bus connections, see the operating instructions for the remote accessories.
REMOTE ON / OFF
9
Using the four DIP switches, the audio signal present at the REMOTE IN can be individually routed to the amplifier channels CH1 to CH4 (ON = function
activated, OFF = function deactivated, DIP switch 1 = CH1, DIP switch 2 = CH2, etc). If an audio signal is present at the REMOTE IN input when the
function is activated, the audio signal present at the line input of the corresponding channel is automatically muted. In this case, REMOTE IN has
priority over all other line inputs.
SERVICE
10
The micro USB interface is reserved for service purposes. Do not try to create a connection to an external device.
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9
ON ON DIP DIP
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1 2 2 3 4 3 4
10
4
5
ON DIP
1 2 3 4
6
4
ON ON DIP DIP
2 3 4
1 2 3 4