Specifications

Bosch Security Systems | 2007-08 | 9922 141 50672en
Plena Loop Amplifier | Installation and User Instructions | Configuration en | 30
5.7.3 Range
You can set the AGC range with the AGC volume
control. The AGC volume control is on the rear of the
loop amplifier (refer to figure 5.6).
The correct AGC range depends on the audio input
signals and the perceptions of the users of the connected
induction loops. If you set the AGC range too wide, soft
sounds (for example, undesired ambient noise) is
amplified. If you set the AGC range too narrow, desired
soft sounds are lost.
5.8 Frequency range
You can set the frequency range with the 5K/10K switch.
The 5K/10K switch is on the rear of the loop amplifier
(refer to figure 5.7).
• If the audio inputs contain speech, set the switch in
the 5K position for the most optimal result.
• If the audio inputs contain background music, set the
switch is in the 10K position for the most optimal
result.
5.9 Audio inputs
5.9.1 Sensitivity
You can set the sensitivity of the audio inputs with the
Mic/Line switch. The Mic/Line switch is on the rear of
the loop amplifier (refer to figure 5.8).
• If the connected audio source is a microphone, set
the switch in the Mic position.
• If the connected audio source is a line-level source,
set the switch in the Line position.
5.9.2 Phantom power
You can switch phantom power for microphones on
and off with the Phantom power switch. The Phantom
power switch is on the rear of the loop amplifier (refer to
figure 5.9).
• If the connected audio source is a microphone that
must receive phantom power, set the Phantom switch
in the ON position.
• If the connected audio source is not a microphone or
if the connected microphone does not accept
phantom power, set the Phantom switch in the OFF
position.
figure 5.6: AGC volume control
figure 5.7: Frequency range switch
AGC
AGC
Limiter 5K 10K
AGC
AGC
Limiter 5K 10K
figure 5.8: Mix/Line switch
figure 5.9: Phantom switch
Vox Mix On Off
Phantom
Mic Line
Vox Mix On Off
Phantom
Mic Line