Configuration
Phantom power
When condenser microphones are connected, you have to press the PHANTOM MIC 1-5
button. The microphone gets its operating voltage (+48 V DC) through the mixer. Phantom
power is activated/deactivated for all 5 MIC/LINE inputs together.
100 V Direct Drive
The 100 V Direct Drive mode of the PM 502 allows connection of 100 V loudspeaker lines in
high impedance mode (High-Z) without using output transformers. In this case the maximum
number of loudspeakers connected to an output channel is only limited by the amplifier‘s
output power. This mode should be used if the distance between the amplifier and the
speaker is larger than 50 meters (approx. 150 feet) and/or a high number of small speakers
with transformers (e.g. ceiling speakers) are used. Depending on the audio signal a 50 Hz or
70 Hz high-pass filter can be selected, the LPN filter is deactivated automatically if the 100 V
Direct Drive mode is activated.
Notice!
70 V loudspeaker lines
Next to 100 V loudspeaker lines it is possible to drive 70 V loudspeaker lines. In this case the
limiter of the channel selected for Amp Routing (e.g. MASTER A) has to be set to +3 dBu in
the OUTPUT SETTINGS LIMITERS dialog.
Please refer to section Menu, page 26, how to activate Direct Drive. When activated, the
100V DIRECT DRIVE indicator on the front panel lights green. For connecting 100 V
loudspeaker lines to the PM 502 please refer to section Speaker connection, page 12.
Amplifier routing
Caution!
Make sure to set both the AUX and MASTER volume controls to their minimum position before
editing the amplifier routing.
The two output channels CH 1/2 of the integrated power amplifier can be used for different
audio signals. Please refer to section Menu, page 26, how to edit the amplifier routing.
Following table lists all amplifier routings available.
Routing Low-Z mode High-Z mode (Direct Drive )
CH 1 CH 2 CH 1 + 2
MASTER A Master A left Master A right Master A summed
MASTER B Master B left Master B right Master B summed
AUX AUX AUX AUX
6
6.1
6.2
6.3
16 en | Configuration PM 502
15-May-14 | 02 | F01U297804 User manual Bosch Sicherheitssysteme GmbH