ITEC SPIDER 44/02 / SPIDER 04/02
www.itec-audio.com
11
SPIDER 44/02 / SPIDER 04/02
Speaker line monitoring (optional)
The speaker line monitoring is a plug-in board that can be optionally
installed in the Spider44 / Spider04. The four zones of the line
monitoring correspond to the respective audio outputs of the Spi-
der44 / Spider04. It will short circuit, earth fault and the speaker line,
but also break-down or change in level of the ampli
fi
er detected.
There are two ways of monitoring line available and therefore the wiring is different:
Line return:
The end of a line speaker wire is guided back to the device. A break is detected when the
transmitted signal cannot be detected at the end of the line. Accordingly, branches and branch lines must be
avoided.
Impedance measurement:
Using this method the impedance of the connected loudspeaker line is
continuously measured in operation and compared with one, once de
fi
ned as a reference impedance value.
Deviations in the range 10 - 20% (adjustable) can reliably be detected. Using the impedance measurement,
the return of the speaker wire to the terminals “RET” can be omitted.
SPIDER
44
/
SPIDER
04
Line Detection (Option)
POWER AMP
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+
-
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-
100 V
AUDIO-OUTPUT
OUT 1