Bosch LBB1970 User Manual

Communication Systems | LBB 1970/00 Plena BGM/Paging System

LBB 1970/00 Plena BGM/Paging System

All-in-one solution for background music and paging

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CD-player for audio and MP3 CD/CD-R

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FM/AM tuner with 15 presets and digital control

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Dual-zone 120 W mixer amplifier with volume control

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per zone
Selectable priority and VOX switching on microphone

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input 1
Optional 2-tone chime to precede announcements

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The Plena BGM/paging system is the versatile all-in-one
solution to cover all needs for background music (BGM),
making announcements and paging people. This high­performance yet affordable unit is very easy to install
and operate.
It is typically used in shops, supermarkets, restaurants,
bars, schools, canteens, gymnasiums, garages and other
places where BGM creates the right atmosphere and
also where amplified speech needs to be clearly heard.

Functions

CD Player
This unit has a CD-player that plays audio CDs and CD-

Rs with MP3-encoded files. It has mono operation in
accordance with public address needs and allows for a
whole day of high-quality uninterrupted music playback
from a single MP3-disc. Music may be organized on a
disc in multiple folders for music selections for different
occasions.

FM/AM Tuner
The digitally controlled FM/AM tuner uses a frequency

synthesizer for accurate capture of radio stations and
has 10 presets for each waveband to store favorite
programs. An auxiliary (music) input and tape output are

provided for connecting external equipment like a DVD­player or cassette deck.

Microphone Inputs
The announcement part of the unit has 3 balanced

microphone inputs. Microphone input 1 has a DIN socket
on the rear for a priority microphone (e.g. the
LBB 1950/00) with selectable priority, 2-tone chime to
precede a priority announcement, speech filter and
phantom power, and a phone jack input on the front for
a dynamic microphone (e.g. the LBC 2900/15) with
selectable VOX activation. Presets are provided for
adjusting the music ducking level and the volume of the
chime. Microphone inputs 2 and 3 have XLR sockets with
selectable phantom power, and are mixed with the
BGM. All microphone inputs and the music source have
their own volume control, with a shared bass and treble
tone control and a shared master volume control.

Outputs
The powerful 120 W output section has two transformer

- isolated 100 V constant voltage outputs for driving
100 V-loudspeakers in two separate zones. The 100 V­technique reduces line losses on longer distances and
allows for easy parallel connection of multiple
loudspeakers. Both zones may be individually selected
from the front panel, and the output level in each zone
can be individually set. Each zone also has a low-voltage

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2 | LBB 1970/00 Plena BGM/Paging System

output for connection to 8 Ohm transformerless
loudspeakers (e.g. consumer-type loudspeakers). A
separate 100 V Call Only output is provided for
addressing an area where BGM is not required but
where priority announcements are. A voltage-free Call
Active contact is available for overriding local volume
controls during priority calls or other purposes. A LED
VU-meter monitors the output.

Certifications and Approvals

EMC emission acc. to EN 55103-1
EMC immunity acc. to EN 55103-2
Safety acc. to EN 60065

Parts Included

Quantity Component
1 LBB 1970/00 PLENA BMG/Paging System

Technical Specifications

Electrical

Mains Voltage 230/115 VAC, ±10%, 50/60 Hz
Max Power Consumption 400 VA
Max/Rated Output Power 180 W / 120 W
Max Mains Inrush Current 8A @ 230 VAC / 16A @ 115 VAC
Performance
Frequency Response 60 Hz – 18 kHz (+1/-3 dB, @ - 10 dB ref. rated

output)
Distortion <1% @ rated output, 1 kHz
Bass Control -8/+8 dB @ 100 Hz
Treble Control -8/+8 dB @ 10 kHz
Inputs
Input 1 (5-pin DIN, balanced with phantom power, 6.3 mm phone jack)
Sensitivity 1 mV
Impedance >1 kOhm
S/N (flat at max volume) 63 dB
S/N (flat at min volume/muted) 75 dB
Headroom 25 dB
Speech Filter -3 dB @ 315 Hz, high-pass,

6 dB / oct
Phantom Power Supply 12 V (5-pin DIN)
VOX (on 6.3 mm phone jack) trigger level 0.4 mV

attack time 200 ms

release time 2 s

ducking level adjustable
Input 2,3 (3-pin XLR, balanced with phantom power)
Sensitivity 1m V
Impedance >1 kOhm
S/N (flat at max volume) 63 dB
S/N (flat at min volume/muted) 75 Db
Headroom 25 dB
Phantom Power Supply 12 V
Auxiliary input (Cinch, stereo converted to mono)
Sensitivity 200 mV
Impedance 22 kOhm
S/N (flat at max volume) 70 dB
S/N (flat at min volume/muted) 75 dB
Headroom 25 dB
Tuner
Tuning Range FM 87.5 - 108 MHz(EUROPE, 50 kHz)

87.5 - 108 MHz(ASIA / USA, 100 kHz)

AM 531 - 1602 kHz(EUROPE, 9 kHz)

530 - 1610 kHz(ASIA / USA, 10 kHz)
Sensitivity
FM 2 µV (26 dB S/N)
AM 30 µV (20 dB S/N)
Performance