Features; Capacity - Bosch Plena LBB 1965 Installation And Operating Manual

Plena Message Manager | Installation and Operating Manual |
The Plena Message Manager functions as an audio source in the overall Plena PA-system. With this unit it is
possible to play, via other Plena units, pre-recorded messages that are triggered from external sources or the unit's
front panel switches.
These pre-recorded messages (that can be made on a PC in .wav-format) can be used for various purposes, e.g.
routine messages or emergency calls. The messages are stored in solid state memories (Eeproms) and are
continuously supervised on availability.
When the message manager is connected to the Plena System Pre-amplifier (LBB1925), it is also possible to
distribute the messages in pre-programmed zones.
The unit is delivered with the mains voltage selector set to 230 Vac. This selector can be set to 115 Vac.
The unit is not provided with a separate power ON indication. One message LED on the front panel will always be
lit (thus functioning as a power ON indication) as at least one message will be loaded. In case no messages are
loaded, this fault situation is indicated by the fault LED.

1. 1 Features

- Up to 12 different messages can be stored.
- Up to 12 message sequences or announcements (each consisting of up to 4 different messages + zone infor-
mation) can be stored.
- Messages can be edited, assembled and uploaded by means of a PC.
- The message content is continuously supervised on availability.
- The cabling of trigger inputs 1 through 6 can be supervised on cuts and short-circuits.
- Mains supply voltage (230/115 Vac) can be supervised.
- Pilot tone can be added to supervise the audio connection to an amplifier or the sound system.
- Internal pilot tone to supervise the internal audio path.
- Support for various sample frequencies to balance audio quality versus message length

1.2 Capacity

The storage device of the messages is a built-in block-erasable EEPROM with fixed storage capacity of 8.38 MByte.
The message manager accepts .wav-files with sample frequencies of 24, 22.050, 16, 12, 11.025 and 8 kHz. The word
length is fixed to 16 bits. This means that the distortion and signal to noise level is of CD quality. Lower sample
frequencies mean a decrease in audio quality (lower bandwidth), but an increase in message length. See the table
below.
Sample frequency
Audio bandwidth (approx.)
Max. length of all 12 messages
Bosch Security Systems | 2003-09 | 9922 141 50502en
24 kHz 22.050 kHz
11 kHz 10 kHz
170 s 180 s
About the equipment
16 kHz 12 kHz
7.3 kHz 5.5 kHz
250 s 335 s
en | 8
11.025 kHz 8 kHz
5 kHz 3.6 kHz
360 s 500 s